abstract stringlengths 3 192k | title stringlengths 4 857 |
|---|---|
we investigate interacting scenarios that belong to a wider class, since they include a dynamical dark energy component whose equation of state follows various one-parameter parametrizations. we confront them with the latest observational data from the cosmic microwave background, the joint light-curve sample from type ia supernovae, baryon acoustic oscillations, hubble parameter measurements from cosmic chronometers (cc), and a gaussian prior on the hubble parameter h0. in all examined scenarios we find a nonzero interaction; nevertheless, the noninteracting case is allowed within 2 σ . concerning the current value of the dark energy equation of state for all combinations of data sets, it always lies in the phantom regime at more than 2-3 standard deviations. finally, for all interacting models, independently of the combination of data sets considered, the estimated values of the present hubble parameter h0 are greater compared to the λ cdm -based planck estimate and close to the local measurements, thus alleviating the h0 tension. | interacting scenarios with dynamical dark energy: observational constraints and alleviation of the h0 tension |
we apply the effective field theory of large-scale structure to analyze the wcdm cosmological model. by using the full shape of the power spectrum and the bao post-reconstruction measurements from boss, the supernovae from pantheon, and a prior from bbn, we set the competitive cmb-independent limit w=-1.046-0.052+0.055 at 68% c.l. after adding the planck cmb data, we find w=-1.023-0.030+0.033 at 68% c.l. our results are obtained using pybird, a new, fast python-based code which we make publicly available. | limits on wcdm from the eftoflss with the pybird code |
the standard cosmological model is in the midst of a stress test, thanks to the tension between supernovae-based measurements of the hubble constant $h_{0}$ and inferences of its values from cosmic microwave background (cmb) anisotropies. numerous explanations for the present-day cosmic acceleration require the presence of a new fundamental scalar field, as do early dark energy (ede) solutions to the hubble tension. this raises the possibility that \textit{multiple} fields cooperatively contribute to the dark energy component in bursts throughout cosmic time due to distinct initial conditions and couplings. here, this cascading dark energy (cde) scenario is illustrated through a realization that effectively reduces to a two-field model, with two epochs in which dark energy is cosmologically significant. the model is compared to measurements of the cmb, baryon acoustic oscillations, and observations of type-ia supernovae. it is found that this scenario ameliorates the hubble tension, improving over purely late-time models of dark energy, and improves agreement between the related rock `n' roll ede scenario and galaxy survey measurements of baryon acoustic oscillations. | cascading dark energy |
type ia supernovae (sne ia) were instrumental in establishing the acceleration of the universe's expansion. by virtue of their combination of distance reach, precision, and prevalence, they continue to provide key cosmological constraints, complementing other cosmological probes. individual sn surveys cover only over about a factor of two in redshift, so compilations of multiple sn datasets are strongly beneficial. we assemble an updated "union" compilation of 2087 cosmologically useful sne ia from 24 datasets ("union3"). we take care to put all sne on the same distance scale and update the light-curve fitting with salt3 to use the full rest-frame optical. over the next few years, the number of cosmologically useful sne ia will increase by more than a factor of ten, and keeping systematic uncertainties subdominant will be more challenging than ever. we discuss the importance of treating outliers, selection effects, light-curve shape and color populations and standardization relations, unexplained dispersion, and heterogeneous observations simultaneously. we present an updated bayesian framework, called unity1.5 (unified nonlinear inference for type-ia cosmology), that incorporates significant improvements in our ability to model selection effects, standardization, and systematic uncertainties compared to earlier analyses. as an analysis byproduct, we also recover the posterior of the sn-only peculiar-velocity field, although we do not interpret it in this work. we compute updated cosmological constraints with union3 and unity1.5, finding weak 1.7--2.6sigma tension with lambdacdm and possible evidence for thawing dark energy. we release our binned sn distances to the community. | union through unity: cosmology with 2,000 sne using a unified bayesian framework |
new light particles produced in supernovae can lead to additional energy loss and a consequent deficit in neutrino production in conflict with the neutrinos observed from supernova 1987a (sn1987a). contrary to the majority of previous sn1987a studies, we examine the impact of z' bosons, axions, and axion-like particles (alps) interacting with the muons produced in sn1987a. for the first time, we find constraints on generic z' bosons coupled to muons, and apply our results to particle models including gauged lμ-lτ number, u (1)lμ-lτ, and gauged b - l number, u(1)b-l. we constrain z' bosons with masses up to about 250 - 500 mev, and down to about 10-9 in z'-muon coupling. we also extend previous work on axion-muon couplings by examining the importance of loop-level interactions, as well as performing calculations over a wider range of axion masses. we constrain muon-coupled axions from arbitrarily low masses up to about 200 - 500 mev, with bounds extending down to axion-muon couplings of approximately 10-8 gev-1. we conclude that supernovae broadly provide a sensitive probe of new lightly-coupled particles interacting with muons. | supernova muons: new constraints on z' bosons, axions and alps |
hyper-kamiokande (hk) is the next generation underground water cherenkov detector that builds on the highly successful super-kamiokande (sk) experiment. the 260,000-ton detector has an 8.4 times larger fiducial volume than its predecessor. hk's low energy threshold combined with the very large fiducial volume make the detector unique; hk is expected to acquire an unprecedented exposure of 3.8 mton-year over a period of 20 years starting in 2027. it has an extremely diverse science program including long-baseline neutrino oscillation measurements, nucleon decay searches, atmospheric neutrinos, neutrinos from the sun and supernova explosions, and neutrinos from other astrophysical origins. like dune, the flagship project of the u.s. high-energy physics program, hk measures fundamental properties of neutrinos such as the search for leptonic cp violation and neutrino physics beyond the standard model. | hyper-kamiokande experiment: a snowmass white paper |
the deep underground neutrino experiment (dune) is a next-generation long-baseline neutrino oscillation experiment with a primary physics goal of observing neutrino and antineutrino oscillation patterns to precisely measure the parameters governing long-baseline neutrino oscillation in a single experiment, and to test the three-flavor paradigm. dune's design has been developed by a large, international collaboration of scientists and engineers to have unique capability to measure neutrino oscillation as a function of energy in a broadband beam, to resolve degeneracy among oscillation parameters, and to control systematic uncertainty using the exquisite imaging capability of massive lartpc far detector modules and an argon-based near detector. dune's neutrino oscillation measurements will unambiguously resolve the neutrino mass ordering and provide the sensitivity to discover cp violation in neutrinos for a wide range of possible values of $\delta_{cp}$. dune is also uniquely sensitive to electron neutrinos from a galactic supernova burst, and to a broad range of physics beyond the standard model (bsm), including nucleon decays. dune is anticipated to begin collecting physics data with phase i, an initial experiment configuration consisting of two far detector modules and a minimal suite of near detector components, with a 1.2 mw proton beam. to realize its extensive, world-leading physics potential requires the full scope of dune be completed in phase ii. the three phase ii upgrades are all necessary to achieve dune's physics goals: (1) addition of far detector modules three and four for a total fd fiducial mass of at least 40 kt, (2) upgrade of the proton beam power from 1.2 mw to 2.4 mw, and (3) replacement of the near detector's temporary muon spectrometer with a magnetized, high-pressure gaseous argon tpc and calorimeter. | snowmass neutrino frontier: dune physics summary |
the gravitationally lensed supernova refsdal appeared in multiple images produced through gravitational lensing by a massive foreground galaxy cluster. after the supernova appeared in 2014, lens models of the galaxy cluster predicted that an additional image of the supernova would appear in 2015, which was subsequently observed. we use the time delays between the images to perform a blinded measurement of the expansion rate of the universe, quantified by the hubble constant (h0). using eight cluster lens models, we infer h0=64.8-4.3+4.4 kilometers per second per megaparsec. using the two models most consistent with the observations, we find h0=66.6-3.3+4.1 kilometers per second per megaparsec. the observations are best reproduced by models that assign dark-matter halos to individual galaxies and the overall cluster. | constraints on the hubble constant from supernova refsdal's reappearance |
we present cosmological parameter constraints obtained from galaxy clusters identified by their sunyaev-zel’dovich effect signature in the 2500 square-degree south pole telescope sunyaev zel’dovich (spt-sz) survey. we consider the 377 cluster candidates identified at z\gt 0.25 with a detection significance greater than five, corresponding to the 95% purity threshold for the survey. we compute constraints on cosmological models using the measured cluster abundance as a function of mass and redshift. we include additional constraints from multi-wavelength observations, including chandra x-ray data for 82 clusters and a weak lensing-based prior on the normalization of the mass-observable scaling relations. assuming a spatially flat λcdm cosmology, we combine the cluster data with a prior on h 0 and find {σ }8=0.784+/- 0.039 and {{{ω }}}m=0.289+/- 0.042, with the parameter combination {σ }8{({{{ω }}}m/0.27)}0.3=0.797+/- 0.031. these results are in good agreement with constraints from the cosmic microwave background (cmb) from spt, wmap, and planck, as well as with constraints from other cluster data sets. we also consider several extensions to λcdm, including models in which the equation of state of dark energy w, the species-summed neutrino mass, and/or the effective number of relativistic species ({n}{eff}) are free parameters. when combined with constraints from the planck cmb, h 0, baryon acoustic oscillation, and sne, adding the spt cluster data improves the w constraint by 14%, to w=-1.023+/- 0.042. | cosmological constraints from galaxy clusters in the 2500 square-degree spt-sz survey |
we present a new calibration of the peak absolute magnitude of type ia supernovae (sne ia) based on the surface brightness fluctuations (sbf) method, aimed at measuring the value of the hubble constant. we build a sample of calibrating anchors consisting of 24 sne hosted in galaxies that have sbf distance measurements. applying a hierarchical bayesian approach, we calibrate the sn ia peak luminosity and extend the hubble diagram into the hubble flow by using a sample of 96 sne ia in the redshift range 0.02 < z < 0.075, which was extracted from the combined pantheon sample. we estimate a value of h0 = 70.50 ± 2.37 (stat.) ± 3.38 (sys.) km s−1 mpc−1 (i.e., 3.4% stat., 4.8% sys.), which is in agreement with the value obtained using the tip of the red giant branch calibration. it is also consistent, within errors, with the value obtained from sne ia calibrated with cepheids or the value inferred from the analysis of the cosmic microwave background. we find that the sne ia distance moduli calibrated with sbf are on average larger by 0.07 mag than those calibrated with cepheids. our results point to possible differences among sne in different types of galaxies, which could originate from different local environments and/or progenitor properties of sne ia. sampling different host galaxy types, sbf offers a complementary approach to using cepheids, which is important in addressing possible systematics. as the sbf method has the ability to reach larger distances than cepheids, the impending entry of the vera c. rubin observatory and jwst into operation will increase the number of sne ia hosted in galaxies where sbf distances can be measured, making sbf measurements attractive for improving the calibration of sne ia, as well as in the estimation of h0. | a new measurement of the hubble constant using type ia supernovae calibrated with surface brightness fluctuations |
we explore cosmological constraints on the sum of the three active neutrino masses mν in the context of dynamical dark energy (dde) models with equation of state (eos) parametrized as a function of redshift z by w (z )=w0+waz /(1 +z ) , and satisfying w (z )≥-1 for all z . we make use of cosmic microwave background data from the planck satellite, baryon acoustic oscillation measurements, and supernovae ia luminosity distance measurements, and perform a bayesian analysis. we show that, within these models, the bounds on mν do not degrade with respect to those obtained in the λ cdm case; in fact, the bounds are slightly tighter, despite the enlarged parameter space. we explain our results based on the observation that, for fixed choices of w0 , wa such that w (z )≥-1 (but not w =-1 for all z ), the upper limit on mν is tighter than the λ cdm limit because of the well-known degeneracy between w and mν. the bayesian analysis we have carried out then integrates over the possible values of w0-wa such that w (z )≥-1 , all of which correspond to tighter limits on mν than the λ cdm limit. we find a 95% credible interval (c.i.) upper bound of mν<0.13 ev . this bound can be compared with the 95% c.i. upper bounds of mν<0.16 ev , obtained within the λ cdm model, and mν<0.41 ev , obtained in a dde model with arbitrary eos (which allows values of w <-1 ). contrary to the results derived for dde models with arbitrary eos, we find that a dark energy component with w (z )≥-1 is unable to alleviate the tension between high-redshift observables and direct measurements of the hubble constant h0. finally, in light of the results of this analysis, we also discuss the implications for dde models of a possible determination of the neutrino mass ordering by laboratory searches. | constraints on the sum of the neutrino masses in dynamical dark energy models with w (z )≥-1 are tighter than those obtained in λ cdm |
the mismatch in the value of the hubble constant from low- and high-redshift observations may be recast as a discrepancy between the low- and high-redshift determinations of the luminosity of type ia supernovae, the latter featuring an absolute magnitude which is ≈0.2 mag lower. here, we propose that a rapid transition in the value of the relative effective gravitational constant μg≡g/effgn at zt≃0.01 could explain the lower luminosity (higher magnitude) of local supernovae, thus solving the h0 crisis. in other words, here the tension is solved by featuring a transition at the perturbative rather than background level. a model that features μg=1 for z ≲0.01 but μg≃0.9 for z ≳0.01 is trivially consistent with local gravitational constraints but would raise the chandrasekhar mass and so decrease the absolute magnitude of type ia supernovae at z ≳0.01 by the required value of ≈0.2 mag . such a rapid transition of the effective gravitational constant would not only resolve the hubble tension but it would also help resolve the growth tension as it would reduce the growth of density perturbations without affecting the planck /λ cdm background expansion. | rapid transition of geff at zt≃0.01 as a possible solution of the hubble and growth tensions |
we investigate constraints on early dark energy (ede) using act dr4, spt-3g 2018, planck polarization, and restricted planck temperature data (at ℓ<650 ), finding a 3.3 σ preference (δ χ2=-16.2 for three additional degrees of freedom) for ede over λ cdm . the ede contributes a maximum fractional energy density of fede(zc)=0.16 3-0.04+0.047 at a redshift zc=3357 ±200 and leads to a cmb inferred value of the hubble constant h0=74.2-2.1+1.9 km /s /mpc . we find that planck and act dr4 data provide the majority of the improvement in χ2, and that the inclusion of spt-3g pulls the posterior of fede(zc) away from λ cdm . this is the first time that a moderate preference for ede has been reported for these combined cmb datasets including planck polarization. we find that including measurements of supernovae luminosity distances and the baryon acoustic oscillation standard ruler only minimally affects the preference (3.0 σ ), while measurements that probe the clustering of matter at late times—the lensing potential power spectrum from planck and f σ8 from boss—decrease the significance of the preference to 2.6 σ . conversely, adding a prior on the h0 value as reported by the s h0es collaboration increases the preference to the 4 -5 σ level. in the absence of this prior, the inclusion of planck tt data at ℓ>1300 reduces the preference from 3.0 σ to 2.3 σ and the constraint on fede(zc) becomes compatible with λ cdm at 1 σ . we explore whether systematic errors in the planck polarization data may affect our conclusions and find that changing the te polarization efficiencies significantly reduces the planck preference for ede. more work will be necessary to establish whether these hints for ede within cmb data alone are the sole results of systematic errors or an opening to new physics. | hints of early dark energy in planck, spt, and act data: new physics or systematics? |
motivated by the current status of cosmological observations and significant tensions in the estimated values of some key parameters assuming the standard λcdm model, we propose a simple but radical phenomenological emergent dark energy model where dark energy has no effective presence in the past and emerges at later times. theoretically, in this phenomenological dark energy model with zero degrees of freedom (similar to a λcdm model), one can derive that the equation of state of dark energy increases from -\tfrac{2}{3{ln} 10}-1 in the past to -1 in the future. we show that by setting a hard-cut 2σ lower bound prior for h 0 associated with a 97.72% probability from recent local observations, this model can satisfy different combinations of cosmological observations at low and high redshifts (sne ia, baryon acoustic oscillation (bao), lyα bao, and cosmic microwave background (cmb)) substantially better than the concordance λcdm model with {{δ }}{χ }{bf}2∼ -41.08 and δ dic ∼ -35.38. if there are no substantial systematics in sn ia, bao, or planck cmb data, and assuming the reliability of current local h 0 measurements, there is a very high probability that with more precise measurements of the hubble constant our proposed phenomenological model rules out the cosmological constant with decisive statistical significance and is a strong alternative to explain the combination of different cosmological observations. this simple phenomenologically emergent dark energy model can guide theoretically motivated dark energy model building activities. | a simple phenomenological emergent dark energy model can resolve the hubble tension |
axion models with generation-dependent peccei-quinn charges can lead to flavor-changing neutral currents, thus motivating qcd axion searches at precision flavor experiments. we rigorously derive limits on the most general effective flavor-violating couplings from current measurements and assess their discovery potential. for two-body decays, we use available experimental data to derive limits on q →q'a decay rates for all flavor transitions. axion contributions to neutral-meson mixing are calculated in a systematic way using chiral perturbation theory and operator product expansion. we also discuss in detail baryonic decays and three-body meson decays, which can lead to the best search strategies for some of the couplings. for instance, a strong limit on the λ →n a transition can be derived from the supernova sn 1987a. in the near future, dedicated searches for q →q'a decays at ongoing experiments could potentially test peccei-quinn breaking scales up to 1012 gev at na62 or koto and up to 109 gev at belle ii or bes iii. | quark flavor phenomenology of the qcd axion |
the ordering of the neutrino masses is a crucial input for a deep understanding of flavor physics, and its determination may provide the key to establish the relationship among the lepton masses and mixings and their analogous properties in the quark sector. the extraction of the neutrino mass ordering is a data-driven field expected to evolve very rapidly in the next decade. in this review, we both analyze the present status and describe the physics of subsequent prospects. firstly, the different current available tools to measure the neutrino mass ordering are described. namely, reactor, long-baseline (accelerator and atmospheric) neutrino beams, laboratory searches for beta and neutrinoless double beta decays and observations of the cosmic background radiation and the large scale structure of the universe are carefully reviewed. secondly, the results from an up-to-date comprehensive global fit are reported: the bayesian analysis to the 2018 publicly available oscillation and cosmological data sets provides strong evidence for the normal neutrino mass ordering versus the inverted scenario, with a significance of 3.5 standard deviations. this preference for the normal neutrino mass ordering is mostly due to neutrino oscillation measurements. finally, we shall also emphasize the future perspectives for unveiling the neutrino mass ordering. in this regard, apart from describing the expectations from the aforementioned probes, we also focus on those arising from alternative and novel methods, as 21 cm cosmology, core-collapse supernova neutrinos and the direct detection of relic neutrinos. | neutrino mass ordering from oscillations and beyond: 2018 status and future prospects |
the isotropy of the late universe and consequently of the x-ray galaxy cluster scaling relations is an assumption greatly used in astronomy. however, within the last decade, many studies have reported deviations from isotropy when using various cosmological probes; a definitive conclusion has yet to be made. new, effective and independent methods to robustly test the cosmic isotropy are of crucial importance. in this work, we use such a method. specifically, we investigate the directional behavior of the x-ray luminosity-temperature (lx-t) relation of galaxy clusters. a tight correlation is known to exist between the luminosity and temperature of the x-ray-emitting intracluster medium of galaxy clusters. while the measured luminosity depends on the underlying cosmology through the luminosity distance dl, the temperature can be determined without any cosmological assumptions. by exploiting this property and the homogeneous sky coverage of x-ray galaxy cluster samples, one can effectively test the isotropy of cosmological parameters over the full extragalactic sky, which is perfectly mirrored in the behavior of the normalization a of the lx-t relation. to do so, we used 313 homogeneously selected x-ray galaxy clusters from the meta-catalogue of x-ray detected clusters of galaxies. we thoroughly performed additional cleaning in the measured parameters and obtain core-excised temperature measurements for all of the 313 clusters. the behavior of the lx-t relation heavily depends on the direction of the sky, which is consistent with previous studies. strong anisotropies are detected at a ≳4σ confidence level toward the galactic coordinates (l, b) ∼ (280°, - 20°), which is roughly consistent with the results of other probes, such as supernovae ia. several effects that could potentially explain these strong anisotropies were examined. such effects are, for example, the x-ray absorption treatment, the effect of galaxy groups and low redshift clusters, core metallicities, and apparent correlations with other cluster properties, but none is able to explain the obtained results. analyzing 105 bootstrap realizations confirms the large statistical significance of the anisotropic behavior of this sky region. interestingly, the two cluster samples previously used in the literature for this test appear to have a similar behavior throughout the sky, while being fully independent of each other and of our sample. combining all three samples results in 842 different galaxy clusters with luminosity and temperature measurements. performing a joint analysis, the final anisotropy is further intensified (∼5σ), toward (l, b) ∼ (303°, - 27°), which is in very good agreement with other cosmological probes. the maximum variation of dl seems to be ∼16 ± 3% for different regions in the sky. this result demonstrates that x-ray studies that assume perfect isotropy in the properties of galaxy clusters and their scaling relations can produce strongly biased results whether the underlying reason is cosmological or related to x-rays. the identification of the exact nature of these anisotropies is therefore crucial for any statistical cluster physics or cosmology study. | probing cosmic isotropy with a new x-ray galaxy cluster sample through the lx-t scaling relation |
new measurements of the expansion rate of the universe have plunged the standard model of cosmology into a severe crisis. in this paper, we propose a simple resolution to the problem that relies on a first order phase transition in a dark sector in the early universe, before recombination. this will lead to a short phase of a new early dark energy (nede) component and can explain the observations. we model the false vacuum decay of the nede scalar field as a sudden transition from a cosmological constant source to a decaying fluid with constant equation of state. the corresponding fluid perturbations are covariantly matched to the adiabatic fluctuations of a subdominant scalar field that triggers the phase transition. fitting our model to measurements of the cosmic microwave background (cmb), baryonic acoustic oscillations (bao, and supernovae (sne) yields a significant improvement of the best fit compared with the standard cosmological model without nede. we find the mean value of the present hubble parameter in the nede model to be h0=71.4 ±1.0 km s-1 mpc-1 (68% c.l.). | new early dark energy |
a population of binary black hole mergers has now been observed in gravitational waves by advanced ligo and virgo. the masses of these black holes appear to show evidence for a pileup between 30 and 45 m ⊙ and a cutoff above ∼45 m ⊙. one possible explanation for such a pileup and subsequent cutoff are pulsational pair-instability supernovae (ppisne) and pair-instability supernovae (pisne) in massive stars. we investigate the plausibility of this explanation in the context of isolated massive binaries. we study a population of massive binaries using the rapid population synthesis software compas, incorporating models for ppisne and pisne. our models predict a maximum black hole mass of 40 m ⊙. we expect ∼10% of all binary black hole mergers at redshift z = 0 will include at least one component that went through a ppisn (with mass 30-40 m ⊙), constituting ∼20%-50% of binary black hole mergers observed during the first two observing runs of advanced ligo and virgo. empirical models based on fitting the gravitational-wave mass measurements to a combination of a power law and a gaussian find a fraction too large to be associated with ppisne in our models. the rates of ppisne and pisne track the low metallicity star formation rate, increasing out to redshift z = 2. these predictions may be tested both with future gravitational-wave observations and with observations of superluminous supernovae. | the impact of pair-instability mass loss on the binary black hole mass distribution |
a universal mechanism may be responsible for several unresolved cosmic conundra. the sudden drop in the pressure of relativistic matter at $w^{\pm}/z^{0}$ decoupling, the quark--hadron transition and $e^{+}e^{-}$ annihilation enhances the probability of primordial black hole (pbh) formation in the early universe. assuming the amplitude of the primordial curvature fluctuations is approximately scale-invariant, this implies a multi-modal pbh mass spectrum with peaks at $10^{-6}$, 1, 30, and $10^{6}\,m_{\odot}$. this suggests a unified pbh scenario which naturally explains the dark matter and recent microlensing observations, the ligo/virgo black hole mergers, the correlations in the cosmic infrared and x-ray backgrounds, and the origin of the supermassive black holes in galactic nuclei at high redshift. a distinctive prediction of our model is that ligo/virgo should observe black hole mergers in the mass gaps between 2 and $5\,m_{\odot}$ (where no stellar remnants are expected) and above $65\,m_{\odot}$ (where pair-instability supernovae occur) and low-mass-ratios in between. therefore the recent detection of events gw190425, gw190814 and gw190521 with these features is striking confirmation of our prediction and may indicate a primordial origin for the black holes. in this case, the exponential sensitivity of the pbh abundance to the equation of state would offer a unique probe of the qcd phase transition. the detection of pbhs would also offer a novel way to probe the existence of new particles or phase transitions with energy between $1\,{\rm mev}$ and $10^{10}\,$gev. | cosmic conundra explained by thermal history and primordial black holes |
simultaneous measurements of distance and redshift can be used to constrain the expansion history of the universe and associated cosmological parameters. merging binary black hole (bbh) systems are standard sirens—their gravitational waveform provides direct information about the luminosity distance to the source. there is, however, a perfect degeneracy between the source masses and redshift; some nongravitational information is necessary to break the degeneracy and determine the redshift of the source. here we suggest that the pair instability supernova (pisn) process, thought to be the source of the observed upper limit on the black hole mass in merging bbh systems at ∼ 45 {m}⊙ , imprints a mass scale in the population of bbh mergers and permits a measurement of the redshift-luminosity-distance relation with these sources. we simulate five years of bbh detections in the advanced ligo and virgo detectors with a realistic bbh merger rate, mass distribution with smooth pisn cutoff, and measurement uncertainty. we show that after one year of operation at design sensitivity the bbh population can constrain h(z) to 6.1 % at a pivot redshift z≃ 0.8. after five years the constraint improves to 2.9 % . if the pisn cutoff is sharp, the uncertainty is smaller by about a factor of two. this measurement relies only on general relativity and the presence of a mass scale that is approximately fixed or calibrated across cosmic time; it is independent of any distance ladder. observations by future “third-generation” gravitational wave detectors, which can see bbh mergers throughout the universe, would permit subpercent cosmographical measurements to z ≳ 4 within one month of observation. | a future percent-level measurement of the hubble expansion at redshift 0.8 with advanced ligo |
gamma-ray bursts (grbs) are among the brightest and most energetic events in the universe. the duration and hardness distribution of grbs has two clusters1, now understood to reflect (at least) two different progenitors2. short-hard grbs (sgrbs; t90 < 2 s) arise from compact binary mergers, and long-soft grbs (lgrbs; t90 > 2 s) have been attributed to the collapse of peculiar massive stars (collapsars)3. the discovery of sn 1998bw/grb 980425 (ref. 4) marked the first association of an lgrb with a collapsar, and at 2017gfo (ref. 5)/grb 170817a/gw170817 (ref. 6) marked the first association of an sgrb with a binary neutron star merger, which also produced a gravitational wave. here, we present the discovery of ztf20abwysqy (at2020scz), a fast-fading optical transient in the fermi satellite and the interplanetary network localization regions of grb 200826a; x-ray and radio emission further confirm that this is the afterglow. follow-up imaging (at rest-frame 16.5 days) reveals excess emission above the afterglow that cannot be explained as an underlying kilonova, but which is consistent with being the supernova. although the grb duration is short (rest-frame t90 of 0.65 s), our panchromatic follow-up data confirm a collapsar origin. grb 200826a is the shortest lgrb found with an associated collapsar; it appears to sit on the brink between a successful and a failed collapsar. our discovery is consistent with the hypothesis that most collapsars fail to produce ultra-relativistic jets. | discovery and confirmation of the shortest gamma-ray burst from a collapsar |
the merging black hole (bh) binaries gw190412, gw190814, and gw190521 from the third ligo/virgo observing run exhibit some extraordinary properties, including highly asymmetric masses, significant spin, and component mass in the 'mass gap'. these features can be explained if one or both components of the binary are the remnants of previous mergers. in this paper, we explore hierarchical mergers in multiple stellar systems, taking into account the natal kick and mass-loss due to the supernova explosion (sn) on each component, as well as the merger kick received by the merger remnant. the binaries that have survived the sne and kicks generally have too wide orbital separations to merge by themselves, but can merge with the aid of an external companion that gives rise to lidov-kozai oscillations. the bh binaries that consist of second-generation bhs can also be assembled in dense star clusters through binary interactions. we characterize the parameter space of these bh binaries by merger fractions in an analytical approach. combining the distributions of the survived binaries, we further constrain the parameters of the external companion, using the analytically formulated tertiary perturbation strength. we find that to produce the three ligo/virgo o3 events, the external companions must be at least a few hundreds m⊙, and fall in the intermediate-mass bh and supermassive bh range. we suggest that gw190412, gw190814, and gw190521 could all be produced via hierarchical mergers in multiples, likely in a nuclear star cluster, with the final merger induced by a massive bh. | hierarchical black hole mergers in multiple systems: constrain the formation of gw190412-, gw190814-, and gw190521-like events |
fast radio bursts (frbs) are one of the most tantalizing mysteries of the radio sky; their progenitors and origins remain unknown and until now no rapid multiwavelength follow-up of an frb has been possible. new instrumentation has decreased the time between observation and discovery from years to seconds, and enables polarimetry to be performed on frbs for the first time. we have discovered an frb (frb 140514) in real-time on 2014 may 14 at 17:14:11.06 utc at the parkes radio telescope and triggered follow-up at other wavelengths within hours of the event. frb 140514 was found with a dispersion measure (dm) of 562.7(6) cm-3 pc, giving an upper limit on source redshift of z ≲ 0.5. frb 140514 was found to be 21 ± 7 per cent (3σ) circularly polarized on the leading edge with a 1σ upper limit on linear polarization <10 per cent. we conclude that this polarization is intrinsic to the frb. if there was any intrinsic linear polarization, as might be expected from coherent emission, then it may have been depolarized by faraday rotation caused by passing through strong magnetic fields and/or high-density environments. frb 140514 was discovered during a campaign to re-observe known frb fields, and lies close to a previous discovery, frb 110220; based on the difference in dms of these bursts and time-on-sky arguments, we attribute the proximity to sampling bias and conclude that they are distinct objects. follow-up conducted by 12 telescopes observing from x-ray to radio wavelengths was unable to identify a variable multiwavelength counterpart, allowing us to rule out models in which frbs originate from nearby (z < 0.3) supernovae and long duration gamma-ray bursts. | a real-time fast radio burst: polarization detection and multiwavelength follow-up |
we systematically study light (<few gev ) dark matter (dm) models that thermalize with visible matter through the higgs portal and identify the remaining gaps in the viable parameter space. such models require a comparably light scalar mediator that mixes with the higgs to avoid dm overproduction and can be classified according to whether this mediator decays (in)visibly. in a representative benchmark model with dirac fermion dm, we find that, even with conservative assumptions about the dm-mediator coupling and mass ratio, the regime in which the mediator is heavier than the dm is fully ruled out by a combination of collider, rare meson decay, and direct detection limits; future and planned experiments including na62 can further improve sensitivity to scenarios in which the higgs portal interaction does not determine the dm abundance. the opposite regime in which the mediator is lighter than the dm and the latter annihilates to pairs of visibly decaying mediators is still viable, but much of the parameter space is covered by rare meson decay, supernova cooling, beam dump, and direct detection constraints. nearly all of these conclusions apply broadly to the simplest variations (e.g., scalar or asymmetric dm). future experiments including ship, news, and super-cdms snolab can greatly improve coverage to this class of models. | probing light thermal dark matter with a higgs portal mediator |
the interaction of supernova ejecta with a surrounding circumstellar medium (csm) generates a strong shock which can convert the ejecta kinetic energy into observable radiation. given the diversity of potential csm structures (arising from diverse mass loss processes such as late-stage stellar outbursts, binary interaction, and winds), the resulting transients can display a wide range of light curve morphologies. we provide a framework for classifying the transients arising from interaction with a spherical csm shell. the light curves are decomposed into five consecutive phases, starting from the onset of interaction and extending through shock breakout and subsequent shock cooling. the relative prominence of each phase in the light curve is determined by two dimensionless quantities representing the csm-to-ejecta mass ratio $\eta$, and a breakout parameter $\xi$. these two parameters define four light curve morphology classes, where each class is characterized by the location of shock breakout and the degree of deceleration as the shock sweeps up the csm. we compile analytic scaling relations connecting the luminosity and duration of each light curve phase to the physical parameters. we then run a grid of radiation hydrodynamics simulations for a wide range of ejecta and csm parameters to numerically explore the landscape of interaction light curves, and to calibrate and confirm the analytic scalings. we connect our theoretical framework to several case studies of observed transients, highlighting the relevance in explaining slow-rising and superluminous supernovae, fast blue optical transients, and double-peaked light curves. | the landscape of thermal transients from supernova interacting with a circumstellar medium |
a simple way of explaining dark matter without modifying known standard model physics is to require the existence of a hidden (dark) sector, which interacts with the visible one predominantly via gravity. we consider a hidden sector containing two stable particles charged under an unbroken u (1 )' gauge symmetry, hence featuring dissipative interactions. the massless gauge field associated with this symmetry, the dark photon, can interact via kinetic mixing with the ordinary photon. in fact, such an interaction of strength ɛ ∼10-9 appears to be necessary in order to explain galactic structure. we calculate the effect of this new physics on big bang nucleosynthesis and its contribution to the relativistic energy density at hydrogen recombination. we then examine the process of dark recombination, during which neutral dark states are formed, which is important for large-scale structure formation. galactic structure is considered next, focusing on spiral and irregular galaxies. for these galaxies we modeled the dark matter halo (at the current epoch) as a dissipative plasma of dark matter particles, where the energy lost due to dissipation is compensated by the energy produced from ordinary supernovae (the core-collapse energy is transferred to the hidden sector via kinetic mixing induced processes in the supernova core). we find that such a dynamical halo model can reproduce several observed features of disk galaxies, including the cored density profile and the tully-fisher relation. we also discuss how elliptical and dwarf spheroidal galaxies could fit into this picture. finally, these analyses are combined to set bounds on the parameter space of our model, which can serve as a guideline for future experimental searches. | dissipative hidden sector dark matter |
we analyse fir dust continuum measurements for 14 galaxies (redshift z ≈ 7) in the alma reionization era bright emission line survey (rebels) large program to derive their physical properties. our model uses three input data, i.e. (a) the uv spectral slope, β, (b) the observed uv continuum flux at 1500 å, f1500, (c) the observed continuum flux at $\approx 158\, \mu$m, f158, and considers milky way (mw) and smc extinction curves, along with different dust geometries. we find that rebels galaxies have 28-90.5 per cent of their star formation obscured; the total (uv+ir) star formation rates are in the range $31.5 \lt {\rm sfr}/({\rm m}_\odot \, {\rm yr}^{-1}) \lt 129.5$. the sample-averaged dust mass and temperature are $(1.3\pm 1.1)\times 10^7 \, \mathrm{m}_\odot$ and 52 ± 11 k, respectively. however, in some galaxies dust is particularly abundant (rebels-14, $m^{\prime }_{\rm d} \approx 3.4 \times 10^7 \, \mathrm{m}_\odot$), or hot (rebels-18, $t^{\prime }_{\rm d} \approx 67$ k). the dust distribution is compact (<0.3 kpc for 70 per cent of the galaxies). the inferred dust yield per supernova is $0.1 \le y_{\rm d}/\, \mathrm{m}_\odot \le 3.3$, with 70 per cent of the galaxies requiring $y_{\rm d} \lt 0.25 \, \mathrm{m}_\odot$. three galaxies (rebels-12, 14, 39) require $y_{\rm d} \gt 1 \, \mathrm{m}_\odot$, which is likely inconsistent with pure sn production, and might require dust growth via accretion of heavy elements from the interstellar medium. with the sfr predicted by the model and a mw extinction curve, rebels galaxies detected in [c ii] nicely follow the local lcii-sfr relation, and are approximately located on the kennicutt-schmidt relation. the sample-averaged gas depletion time is $0.11\, y_{\rm p}^{-2}$ gyr, where yp is the ratio of the gas-to-stellar distribution radius. for some systems, a solution simultaneously matching the observed (β, f1500, f158) values cannot be found. this occurs when the index im = (f158/f1500)/(β - βint), where βint is the intrinsic uv slope, exceeds $i_m^{*}\approx 1120$ for an mw curve. for these objects, we argue that the fir and uv emitting regions are not co-spatial, questioning the use of the irx-β relation. | the alma rebels survey. epoch of reionization giants: properties of dusty galaxies at z ≈ 7 |
we have conducted a new search for the diffuse supernova neutrino background (dsnb) flux at super-kamiokande (sk), with a 22.5 ×2970 -kton .day exposure from its fourth operational phase iv. with the new analysis we improve on the existing background reduction techniques and systematic uncertainties and take advantage of an improved neutron tagging algorithm to lower the energy threshold compared to the previous phases of sk. this allows for setting the world's most stringent upper limit on the extraterrestrial ν¯e flux, for neutrino energies below 31.3 mev. the sk-iv results are combined with the ones from the first three phases of sk to perform a joint analysis using 22.5 ×5823 kton .days of data. this analysis has the world's best sensitivity to the dsnb ν¯e flux, comparable to the predictions from various models. for neutrino energies larger than 17.3 mev, the new combined 90% cl upper limits on the dsnb ν¯e flux lie around 2.7 cm-2.sec-1 , strongly disfavoring the most optimistic predictions. finally, potentialities of the gadolinium phase of sk and the future hyper-kamiokande experiment are discussed. | diffuse supernova neutrino background search at super-kamiokande |
majoron-like bosons would emerge from a supernova (sn) core by neutrino coalescence of the form ν ν →ϕ and ν ¯ν ¯→ϕ with 100-mev-range energies. subsequent decays to (anti)neutrinos of all flavors provide a flux component with energies much larger than the usual flux from the "neutrino sphere." the absence of 100-mev-range events in the kamiokande-ii and irvine-michigan-brookhaven signal of sn 1987a implies that less than 1% of the total energy was thus emitted and provides the strongest constraint on the majoron-neutrino coupling of g ≲10-9 mev /mϕ for 100 ev ≲mϕ≲100 mev . it is straightforward to extend our new argument to other hypothetical feebly interacting particles. | strong supernova 1987a constraints on bosons decaying to neutrinos |
type ia supernovae (sne ia) are considered the most reliable \textit{standard candles} and they have played an invaluable role in cosmology since the discovery of the universe's accelerated expansion. during the last decades, the sne ia samples have been improved in number, redshift coverage, calibration methodology, and systematics treatment. these efforts led to the most recent \textit{``pantheon"} (2018) and \textit{``pantheon +"} (2022) releases, which enable to constrain cosmological parameters more precisely than previous samples. in this era of precision cosmology, the community strives to find new ways to reduce uncertainties on cosmological parameters. to this end, we start our investigation even from the likelihood assumption of gaussianity, implicitly used in this domain. indeed, the usual practise involves constraining parameters through a gaussian distance moduli likelihood. this method relies on the implicit assumption that the difference between the distance moduli measured and the ones expected from the cosmological model is gaussianly distributed. in this work, we test this hypothesis for both the \textit{pantheon} and \textit{pantheon +} releases. we find that in both cases this requirement is not fulfilled and the actual underlying distributions are a logistic and a student's t distribution for the \textit{pantheon} and \textit{pantheon +} data, respectively. when we apply these new likelihoods fitting a flat $\lambda$cdm model, we significantly reduce the uncertainties on $\omega_m$ and $h_0$ of $\sim 40 \%$. this boosts the sne ia power in constraining cosmological parameters, thus representing a huge step forward to shed light on the current debated tensions in cosmology. | reduced uncertainties up to 43\\% on the hubble constant and the matter density with the sne ia with a new statistical analysis |
we present hubble space telescope imaging confirming the optical disappearance of the failed supernova (sn) candidate identified by gerke, kochanek & stanek. this ∼25 m⊙ red supergiant experienced a weak ∼106 l⊙ optical outburst in 2009 and is now at least 5 mag fainter than the progenitor in the optical. the mid-ir flux has slowly decreased to the lowest levels since the first measurements in 2004. there is faint (2000-3000 l⊙) near-ir emission likely associated with the source. we find the late-time evolution of the source to be inconsistent with obscuration from an ejected, dusty shell. models of the spectral energy distribution indicate that the remaining bolometric luminosity is >6 times fainter than that of the progenitor and is decreasing as ∼t-4/3. we conclude that the transient is unlikely to be an sn impostor or stellar merger. the event is consistent with the ejection of the envelope of a red supergiant in a failed sn and the late-time emission could be powered by fallback accretion on to a newly formed black hole. future ir and x-ray observations are needed to confirm this interpretation of the fate for the star. | the search for failed supernovae with the large binocular telescope: confirmation of a disappearing star |
we investigate the observational constraints on an interacting vacuum energy scenario with two different neutrino schemes (with and without a sterile neutrino) using the most recent data from cosmic microwave background (cmb) temperature and polarization anisotropy, baryon acoustic oscillations (bao), type ia supernovae from jla sample and structure growth inferred from cluster counts. we find that inclusion of the galaxy clusters data with the minimal data combination cmb +bao +jla suggests an interaction in the dark sector, implying the decay of dark matter particles into dark energy, since the constraints obtained by including the galaxy clusters data yield a non-null and negative coupling parameter between the dark components at 99% confidence level. we deduce that the current tensions on the parameters h0 and σ8 can be alleviated within the framework of the interacting as well as noninteracting vacuum energy models with sterile neutrinos. | echo of interactions in the dark sector |
as cosmological data have improved, tensions have arisen. one such tension is the difference between the locally measured hubble constant h0 and the value inferred from the cosmic microwave background (cmb). interacting radiation has been suggested as a solution, but studies show that conventional models are precluded by high-ℓ cmb polarization data. it seems at least plausible that a solution may be provided by related models that distinguish between high- and low-ℓ multipoles. when interactions of strongly-coupled radiation are mediated by a force carrier that becomes nonrelativistic, the dark radiation undergoes a "step" in which its relative energy density increases as the mediator deposits its entropy into the lighter species. if this transition occurs while cmb-observable modes are inside the horizon, high- and low-ℓ peaks are impacted differently, corresponding to modes that enter the horizon before or after the step. these dynamics are naturally packaged into the simplest supersymmetric theory, the wess-zumino model, with the mass of the scalar mediator near the ev scale. we investigate the cosmological signatures of such wess-zumino dark radiation (wzdr) and find that it provides an improved fit to the cmb alone, favoring larger values of h0. if supernovae measurements from the sh0es collaboration are also included in the analysis, the inferred value of h0 is yet larger, but the preference for dark radiation and the location of the transition is left nearly unchanged. utilizing a standardized set of measures, we compare to other models and find that wzdr is among the most successful at addressing the h0 tension and is the best of those with a lagrangian formulation. | a step in understanding the hubble tension |
we use luminous red galaxies selected from the imaging surveys that are being used for targeting by the dark energy spectroscopic instrument (desi) in combination with cmb lensing maps from the planck collaboration to probe the amplitude of large-scale structure over 0.4 ≤ z ≤ 1. our galaxy sample, with an angular number density of approximately 500 deg-2 over 18,000 sq.deg., is divided into 4 tomographic bins by photometric redshift and the redshift distributions are calibrated using spectroscopy from desi. we fit the galaxy autospectra and galaxy-convergence cross-spectra using models based on cosmological perturbation theory, restricting to large scales that are expected to be well described by such models. within the context of λcdm, combining all 4 samples and using priors on the background cosmology from supernova and baryon acoustic oscillation measurements, we find s 8 = σ8(ωm/0.3)0.5 = 0.73 ± 0.03. this result is lower than the prediction of the λcdm model conditioned on the planck data. our data prefer a slower growth of structure at low redshift than the model predictions, though at only modest significance. | cosmological constraints from the tomographic cross-correlation of desi luminous red galaxies and planck cmb lensing |
we present cosmological constraints on the sum of neutrino masses as a function of the neutrino lifetime, in a framework in which neutrinos decay into dark radiation after becoming non-relativistic. we find that in this regime the cosmic microwave background (cmb), baryonic acoustic oscillations (bao) and (uncalibrated) luminosity distance to supernovae from the pantheon catalog constrain the sum of neutrino masses ∑mν to obey ∑mν< 0.42 ev at (95% c.l.). while the bound has improved significantly as compared to the limits on the same scenario from planck 2015, it still represents a significant relaxation of the constraints as compared to the stable neutrino case. we show that most of the improvement can be traced to the more precise measurements of low-ℓ polarization data in planck 2018, which leads to tighter constraints on τreio (and thereby on as), breaking the degeneracy arising from the effect of (large) neutrino masses on the amplitude of the cmb power spectrum. | improved cosmological constraints on the neutrino mass and lifetime |
we present a new technique to create a bin-averaged hubble diagram (hd) from photometrically identified sn ia data. the resulting hd is corrected for selection biases and contamination from core-collapse (cc) sne, and can be used to infer cosmological parameters. this method, called “beams with bias corrections” (bbc), includes two fitting stages. the first bbc fitting stage uses a posterior distribution that includes multiple sn likelihoods, a monte carlo simulation to bias-correct the fitted salt-ii parameters, and cc probabilities determined from a machine-learning technique. the bbc fit determines (1) a bin-averaged hd (average distance versus redshift), and (2) the nuisance parameters α and β, which multiply the stretch and color (respectively) to standardize the sn brightness. in the second stage, the bin-averaged hd is fit to a cosmological model where priors can be imposed. we perform high-precision tests of the bbc method by simulating large (150,000 event) data samples corresponding to the dark energy survey supernova program. our tests include three models of intrinsic scatter, each with two different cc rates. in the bbc fit, the salt-ii nuisance parameters α and β are recovered to within 1% of their true values. in the cosmology fit, we determine the dark energy equation of state parameter w using a fixed value of {{{ω }}}{{m}} as a prior: averaging over all six tests based on 6 × 150,000 = 900,000 sne, there is a small w-bias of 0.006+/- 0.002. finally, the bbc fitting code is publicly available in the snana package. | correcting type ia supernova distances for selection biases and contamination in photometrically identified samples |
long-duration (>2 s) γ-ray bursts that are believed to originate from the death of massive stars are expected to be accompanied by supernovae. grb 060614, that lasted 102 s, lacks a supernova-like emission down to very stringent limits and its physical origin is still debated. here we report the discovery of near-infrared bump that is significantly above the regular decaying afterglow. this red bump is inconsistent with even the weakest known supernova. however, it can arise from a li-paczyński macronova--the radioactive decay of debris following a compact binary merger. if this interpretation is correct, grb 060614 arose from a compact binary merger rather than from the death of a massive star and it was a site of a significant production of heavy r-process elements. the significant ejected mass favours a black hole-neutron star merger but a double neutron star merger cannot be ruled out. | a possible macronova in the late afterglow of the long-short burst grb 060614 |
the runaway collision scenario is one of the most promising mechanisms to explain the formation of intermediate-mass black holes (imbhs) in young dense star clusters. on the other hand, the massive stars that participate in the runaway collisions lose mass by stellar winds. in this paper, we discuss new n-body simulations of massive (6.5 × 104 m⊙) star clusters, in which we added upgraded recipes for stellar winds and supernova explosion at different metallicity. we follow the evolution of the principal collision product (pcp), through dynamics and stellar evolution, till it forms a stellar remnant. at solar metallicity, the mass of the final merger product spans from few solar masses up to ∼30 m⊙. at low metallicity (0.01-0.1 z⊙) the maximum remnant mass is ∼250 m⊙, in the range of imbhs. a large fraction (∼0.6) of the pcps are not ejected from the parent star cluster and acquire stellar or black hole (bh) companions. most of the long-lived binaries hosting a pcp are bh-bh binaries. we discuss the importance of this result for gravitational wave detection. | massive black hole binaries from runaway collisions: the impact of metallicity |
in anticipation of the upcoming deployment of the james webb space telescope (jwst), we present high-redshift predictions by the well-established santa cruz semi-analytic model. we update the models by re-calibrating them after adopting cosmological parameters consistent with recent constraints from planck. we provide predictions for rest-frame uv luminosity functions for galaxy populations over a wide range of muv from ∼-6 to ∼-24 between z = 4-10. in addition, we present the corresponding predictions for observed-frame galaxy number counts in different redshift bins in the full set of nircam filters. we provide predictions of the quantitative effect on these observables of varying the physical recipes implemented in the models, such as the molecular gas depletion time (star formation efficiency), scalings or the scalings of outflow rates driven by stars, and supernovae with galaxy circular velocity. based on these results, we discuss what may be learned about the physical processes that shape galaxy formation from jwst observations of galaxy number densities at different intrinsic luminosities. all data tables for the results presented in this work are available at https://www.simonsfoundation.org/semi-analytic-forecasts-for-jwst/. | semi-analytic forecasts for jwst - i. uv luminosity functions at z = 4-10 |
a dense neutrino medium could experience self-induced flavor conversions on relatively small scales in the presence of the so-called fast flavor conversion modes. owing to the fact that fast conversion scales could be much smaller than the ones of the traditional collective neutrino oscillations, it has been speculated that fast modes could lead to some sort of flavor decoherence/equilibrium. we study the evolution of fast modes in the nonlinear regime and we show that not only fast modes are not guaranteed to lead to flavor equilibrium, but also they could lead to some sort of collective neutrino oscillations but on scales determined by neutrino number density. for the νe dominated case, we observe large amplitude collective oscillations, whereas a sort of flavor stabilization is reached for the νbare dominated case. | on fast neutrino flavor conversion modes in the nonlinear regime |
the flavor evolution of neutrinos in core collapse supernovae and neutron star mergers is a critically important unsolved problem in astrophysics. following the electron flavor evolution of the neutrino system is essential for calculating the thermodynamics of compact objects as well as the chemical elements they produce. accurately accounting for flavor transformation in these environments is challenging for a number of reasons, including the large number of neutrinos involved, the small spatial scale of the oscillation, and the nonlinearity of the system. we take a step in addressing these issues by presenting a method which describes the neutrino fields in terms of angular moments. we apply our moment method to neutron star merger conditions and show it simulates fast flavor neutrino transformation in a region where this phenomenon is expected to occur. by comparing with particle-in-cell calculations we show that the moment method is able to capture the three phases of growth, saturation, and decoherence, and correctly predicts the lengthscale of the fastest growing fluctuations in the neutrino field. | neutrino fast flavor instability in three dimensions for a neutron star merger |
we report the classification of the nearby (~6.4 mpc) supernova sn 2023ixf as type ii using the liverpool telescope. the spectrum shows strong flash-ionization features of h, he, c, and n. | lt classification of sn 2023ixf as a type ii supernova in m101 |
stellar-mass black holes are the final remnants of stars born with more than 15 solar masses. billions are expected to reside in the local group, yet only a few are known, mostly detected through x-rays emitted as they accrete material from a companion star. here, we report on vfts 243: a massive x-ray-faint binary in the large magellanic cloud. with an orbital period of 10.4 d, it comprises an o-type star of 25 solar masses and an unseen companion of at least nine solar masses. our spectral analysis excludes a non-degenerate companion at a 5σ confidence level. the minimum companion mass implies that it is a black hole. no other x-ray-quiet black hole is unambiguously known outside our galaxy. the (near-)circular orbit and kinematics of vfts 243 imply that the collapse of the progenitor into a black hole was associated with little or no ejected material or black-hole kick. identifying such unique binaries substantially impacts the predicted rates of gravitational-wave detections and properties of core-collapse supernovae across the cosmos. | an x-ray-quiet black hole born with a negligible kick in a massive binary within the large magellanic cloud |
we review the role that magnetic field may have on the formation and evolution of molecular clouds. after a brief presentation and main assumptions leading to ideal mhd equations, their most important correction, namely the ion-neutral drift is described. the nature of the multi-phase interstellar medium (ism) and the thermal processes that allows this gas to become denser are presented. then we discuss our current knowledge of compressible magnetized turbulence, thought to play a fundamental role in the ism. we also describe what is known regarding the correlation between the magnetic and the density fields. then the influence that magnetic field may have on the interstellar filaments and the molecular clouds is discussed, notably the role it may have on the prestellar dense cores as well as regarding the formation of stellar clusters. finally we briefly review its possible effects on the formation of molecular clouds themselves. we argue that given the magnetic intensities that have been measured, it is likely that magnetic field is i) responsible of reducing the star formation rate in dense molecular cloud gas by a factor of a few, ii) strongly shaping the interstellar gas by generating a lot of filaments and reducing the numbers of clumps, cores and stars, although its exact influence remains to be better understood. moreover at small scales, magnetic braking is likely a dominant process that strongly modifies the outcome of the star formation process. finally, we stress that inducing the formation of more massive stars, magnetic field could possibly enhance the impact of stellar feedback. | the role of magnetic field in molecular cloud formation and evolution |
we measure escape fractions, fesc, of ionizing radiation from galaxies in the sphinx suite of cosmological radiation-hydrodynamical simulations of reionization, resolving haloes with $m_{\rm vir}\gtrsim 7.5 \times 10^7 \ {\rm {m}_{\odot }}$ with a minimum cell width of ≈10 pc. our new and largest 20 co-moving mpc wide volume contains tens of thousands of star-forming galaxies with halo masses up to a few times 1011 m⊙. the simulated galaxies agree well with observational constraints of the ultraviolet (uv) luminosity function in the epoch of reionization. the escape fraction fluctuates strongly in individual galaxies over time-scales of a few myr, due to its regulation by supernova and radiation feedback, and at any given time a tiny fraction of star-forming galaxies emits a large fraction of the ionizing radiation escaping into the intergalactic medium. statistically, fesc peaks in intermediate-mass, intermediate-brightness, and low-metallicity galaxies (m* ≈ 107 m⊙, m1500 ≈ -17, z ≲ 5 × 10-3 z⊙), dropping strongly for lower and higher masses, brighter and dimmer galaxies, and more metal-rich galaxies. the escape fraction correlates positively with both the short-term and long-term specific star formation rate. according to sphinx, galaxies too dim to be yet observed, with ${m_{1500}}\gtrsim -17$, provide about 55 per cent of the photons contributing to reionization. the global averaged fesc naturally decreases with decreasing redshift, as predicted by uv background models and low-redshift observations. this evolution is driven by decreasing specific star formation rates over cosmic time. | lyc escape from sphinx galaxies in the epoch of reionization |
we study the implementation of mechanical feedback from supernovae (sne) and stellar mass loss in galaxy simulations, within the feedback in realistic environments (fire) project. we present the fire-2 algorithm for coupling mechanical feedback, which can be applied to any hydrodynamics method (e.g. fixed-grid, moving-mesh, and mesh-less methods), and black hole as well as stellar feedback. this algorithm ensures manifest conservation of mass, energy, and momentum, and avoids imprinting `preferred directions' on the ejecta. we show that it is critical to incorporate both momentum and thermal energy of mechanical ejecta in a self-consistent manner, accounting for sne cooling radii when they are not resolved. using idealized simulations of single sn explosions, we show that the fire-2 algorithm, independent of resolution, reproduces converged solutions in both energy and momentum. in contrast, common `fully thermal' (energy-dump) or `fully kinetic' (particle-kicking) schemes in the literature depend strongly on resolution: when applied at mass resolution ≳100 m⊙, they diverge by orders of magnitude from the converged solution. in galaxy-formation simulations, this divergence leads to orders-of-magnitude differences in galaxy properties, unless those models are adjusted in a resolution-dependent way. we show that all models that individually time-resolve sne converge to the fire-2 solution at sufficiently high resolution (<100 m⊙). however, in both idealized single-sn simulations and cosmological galaxy-formation simulations, the fire-2 algorithm converges much faster than other sub-grid models without re-tuning parameters. | how to model supernovae in simulations of star and galaxy formation |
multi-dimensional fluid flow plays a paramount role in the explosions of massive stars as core-collapse supernovae. in recent years, three-dimensional (3d) simulations of these phenomena have matured significantly. considerable progress has been made towards identifying the ingredients for shock revival by the neutrino-driven mechanism, and successful explosions have already been obtained in a number of self-consistent 3d models. these advances also bring new challenges, however. prompted by a need for increased physical realism and meaningful model validation, supernova theory is now moving towards a more integrated view that connects multi-dimensional phenomena in the late convective burning stages prior to collapse, the explosion engine, and mixing instabilities in the supernova envelope. here we review our current understanding of multi-d fluid flow in core-collapse supernovae and their progenitors. we start by outlining specific challenges faced by hydrodynamic simulations of core-collapse supernovae and of the late convective burning stages. we then discuss recent advances and open questions in theory and simulations. | hydrodynamics of core-collapse supernovae and their progenitors |
supernova (sn) feedback is one of the key processes shaping the interstellar medium (ism) of galaxies. sne contribute to (and in some cases may dominate) driving turbulence in the ism and accelerating galactic winds. modern cosmological simulations have sufficient resolution to capture the main structures in the ism of galaxies, but are typically still not capable of explicitly resolving all of the small-scale stellar feedback processes, including the expansion of supernova remnants (snrs). we perform a series of controlled three-dimensional hydrodynamic (adaptive mesh refinement) simulations of single snrs expanding in an inhomogeneous density field with statistics motivated by those of the turbulent ism. we use these to quantify the momentum and thermal energy injection from sne as a function of spatial scale and the density, metallicity, and structure of the ambient medium. we develop a series of analytic formulae that we fit to the simulations. these formulae can be used as a basis for a more predictive sub-resolution model for sn feedback for galaxy formation simulations. we then use simulations of multiple, stochastically driven sne that resolve the key phases of snrs to test the sub-resolution model, and show that it accurately captures the turbulent kinetic energy and thermal energy in the ism. by contrast, proposed sn feedback models in the literature based on `delayed cooling' significantly overpredict the late-time thermal energy and momentum in snrs. | supernova feedback in an inhomogeneous interstellar medium |
we present predictions for the evolution of the galaxy dust-to-gas ratio (dgr) and dust-to-metal ratio (dtm) from z = 0 → 6, using a model for the production, growth, and destruction of dust grains implemented into the simba cosmological hydrodynamic galaxy formation simulation. in our model, dust forms in stellar ejecta, grows by the accretion of metals, and is destroyed by thermal sputtering and supernovae. our simulation reproduces the observed dust mass function at z = 0, but modestly underpredicts the mass function by ∼×3 at z ∼ 1-2. the z = 0 dgr versus metallicity relationship shows a tight positive correlation for star-forming galaxies, while it is uncorrelated for quenched systems. there is little evolution in the dgr-metallicity relationship between z = 0 and 6. we use machine learning techniques to search for the galaxy physical properties that best correlate with the dgr and dtm. we find that the dgr is primarily correlated with the gas-phase metallicity, though correlations with the depletion time-scale, stellar mass, and gas fraction are non-negligible. we provide a crude fitting relationship for dgr and dtm versus the gas-phase metallicity, along with a public code package that estimates the dgr and dtm given a set of galaxy physical properties. | the dust-to-gas and dust-to-metal ratio in galaxies from z = 0 to 6 |
we make use of atacama large millimeter/submillimeter array continuum observations of 15 luminous lyman-break galaxies at z ~ 7-8 to probe their dust-obscured star formation. these observations are sensitive enough to probe obscured star formation rates (sfrs) of 20 m ⊙ yr-1 (3σ). six of the targeted galaxies show significant (≥3σ) dust-continuum detections, more than doubling the number of known dust-detected galaxies at z > 6.5. their ir luminosities range from 2.7 × 1011 l ⊙ to 1.1 × 1012 l ⊙, equivalent to obscured sfrs of 25 to 101 m ⊙ yr-1. we use our results to quantify the correlation of the infrared excess (irx) on the uv-continuum slope β uv and stellar mass. our results are most consistent with a small magellanic cloud (smc) attenuation curve for intrinsic uv-slopes ${\beta }_{\mathrm{uv},\mathrm{intr}}$ of -2.63 and most consistent with an attenuation curve in between smc and calzetti for ${\beta }_{\mathrm{uv},\mathrm{intr}}$ slopes of -2.23, assuming a dust temperature tdof 50 k. our fiducial irx-stellar mass results at z ~ 7-8 are consistent with marginal evolution from z ~ 0. we then show how both results depend on td . for our six dust-detected sources, we estimate their dust masses and find that they are consistent with dust production from supernovae if the dust destruction is low (<90%). finally we determine the contribution of dust-obscured star formation to the sfr density for uv luminous (h<-21.5 mag: ≳1.7 l * uv) z ~ 7-8 galaxies, finding that the total sfr density at z ~ 7 and z ~ 8 from bright galaxies is ${0.20}_{-0.10}^{+0.10}$ dex and ${0.23}_{-0.09}^{+0.06}$ dex higher, respectively; i.e., ~ $\tfrac{1}{3}$ of the star formation in ≳1.7 l * uv galaxies at z ~ 7-8 is obscured by dust. | significant dust-obscured star formation in luminous lyman-break galaxies at z 7-8 |
much of the progress made in time-domain astronomy is accomplished by relating observational multiwavelength time-series data to models derived from our understanding of physical laws. this goal is typically accomplished by dividing the task in two: collecting data (observing), and constructing models to represent that data (theorizing). owing to the natural tendency for specialization, a disconnect can develop between the best available theories and the best available data, potentially delaying advances in our understanding new classes of transients. we introduce mosfit: the modular open source fitter for transients, a python-based package that downloads transient data sets from open online catalogs (e.g., the open supernova catalog), generates monte carlo ensembles of semi-analytical light-curve fits to those data sets and their associated bayesian parameter posteriors, and optionally delivers the fitting results back to those same catalogs to make them available to the rest of the community. mosfit is designed to help bridge the gap between observations and theory in time-domain astronomy; in addition to making the application of existing models and creation of new models as simple as possible, mosfit yields statistically robust predictions for transient characteristics, with a standard output format that includes all the setup information necessary to reproduce a given result. as large-scale surveys such as that conducted with the large synoptic survey telescope (lsst), discover entirely new classes of transients, tools such as mosfit will be critical for enabling rapid comparison of models against data in statistically consistent, reproducible, and scientifically beneficial ways. | mosfit: modular open source fitter for transients |
magnetohydrodynamic turbulence is important in many high-energy astrophysical systems, where instabilities can amplify the local magnetic field over very short timescales. specifically, the magnetorotational instability and dynamo action have been suggested as a mechanism for the growth of magnetar-strength magnetic fields (of 1015 gauss and above) and for powering the explosion of a rotating massive star. such stars are candidate progenitors of type ic-bl hypernovae, which make up all supernovae that are connected to long γ-ray bursts. the magnetorotational instability has been studied with local high-resolution shearing-box simulations in three dimensions, and with global two-dimensional simulations, but it is not known whether turbulence driven by this instability can result in the creation of a large-scale, ordered and dynamically relevant field. here we report results from global, three-dimensional, general-relativistic magnetohydrodynamic turbulence simulations. we show that hydromagnetic turbulence in rapidly rotating protoneutron stars produces an inverse cascade of energy. we find a large-scale, ordered toroidal field that is consistent with the formation of bipolar magnetorotationally driven outflows. our results demonstrate that rapidly rotating massive stars are plausible progenitors for both type ic-bl supernovae and long γ-ray bursts, and provide a viable mechanism for the formation of magnetars. moreover, our findings suggest that rapidly rotating massive stars might lie behind potentially magnetar-powered superluminous supernovae. | a large-scale dynamo and magnetoturbulence in rapidly rotating core-collapse supernovae |
analyses of the full shape of the baryon oscillation spectroscopic survey (boss) dr12 power spectrum using the one-loop prediction from the effective field theory of large-scale structures (eftboss) have led to new constraints on extensions to the λ cold dark matter model, such as early dark energy (ede), which has been suggested as a resolution to the "hubble tension." in this paper, we reassess the constraining power of the eftboss on ede in light of a correction to the normalization of boss window functions. overall we find that constraints from eftboss on ede are weakened and represent a small change compared to constraints from planck and the conventional baryon acoustic oscillation /f σ8 measurements. the combination of planck data with eftboss provides a bound on the maximal fractional contribution of ede fede<0.083 at 95% c.l. (compared to <0.054 with the incorrect normalization and <0.088 without full-shape data) and the hubble tension is reduced to 2.1 σ . however, the more extreme model favored by an analysis with just data from the atacama cosmology telescope is disfavored by the eftboss data. we also show that the updated pantheon +type ia supernova (sn1a) analysis can slightly increase the constraints on ede. yet, the inclusion of the sn1a magnitude calibration by sh0es strongly increases the preference for ede to above 5 σ , yielding fede∼0.12-0.02+0.03 around the redshift zc=4365-1100+3000 . our results demonstrate that eftboss data (alone or combined with planck data) do not exclude the ede resolution of the hubble tension. | updated constraints from the effective field theory analysis of the boss power spectrum on early dark energy |
context. gravitational microlensing is sensitive to compact-object lenses in the milky way, including white dwarfs, neutron stars, or black holes, and could potentially probe a wide range of stellar-remnant masses. however, the mass of the lens can be determined only in very limited cases, due to missing information on both source and lens distances and their proper motions.aims: our aim is to improve the mass estimates in the annual parallax microlensing events found in the eight years of ogle-iii observations towards the galactic bulge with the use of gaia data release 2 (dr2).methods: we use gaia dr2 data on distances and proper motions of non-blended sources and recompute the masses of lenses in parallax events. we also identify new events in that sample which are likely to have dark lenses; the total number of such events is now 18.results: the derived distribution of masses of dark lenses is consistent with a continuous distribution of stellar-remnant masses. a mass gap between neutron star and black hole masses in the range between 2 and 5 solar masses is not favoured by our data, unless black holes receive natal kicks above 20-80 km s-1. we present eight candidates for objects with masses within the putative mass gap, including a spectacular multi-peak parallax event with mass of 2.4-1.3+1.9 m⊙ located just at 600 pc. the absence of an observational mass gap between neutron stars and black holes, or conversely the evidence of black hole natal kicks if a mass gap is assumed, can inform future supernova modelling efforts. | constraining the masses of microlensing black holes and the mass gap with gaia dr2 |
we address the problem of the origin of massive stars, namely the origin, path, and timescale of the mass flows that create them. based on extensive numerical simulations, we propose a scenario where massive stars are assembled by large-scale, converging, inertial flows that naturally occur in supersonic turbulence. we refer to this scenario of massive-star formation as the inertial-inflow model. this model stems directly from the idea that the mass distribution of stars is primarily the result of turbulent fragmentation. under this hypothesis, the statistical properties of turbulence determine the formation timescale and mass of prestellar cores, posing definite constraints on the formation mechanism of massive stars. we quantify such constraints by analyzing a simulation of supernova-driven turbulence in a 250 pc region of the interstellar medium, describing the formation of hundreds of massive stars over a time of approximately 30 myr. due to the large size of our statistical sample, we can say with full confidence that massive stars in general do not form from the collapse of massive cores nor from competitive accretion, as both models are incompatible with the numerical results. we also compute synthetic continuum observables in the herschel and alma bands. we find that, depending on the distance of the observed regions, estimates of core mass based on commonly used methods may exceed the actual core masses by up to two orders of magnitude and that there is essentially no correlation between estimated and real core masses. | the origin of massive stars: the inertial-inflow model |
a new class of ultra-long-duration (more than 10,000 seconds) γ-ray bursts has recently been suggested. they may originate in the explosion of stars with much larger radii than those producing normal long-duration γ-ray bursts or in the tidal disruption of a star. no clear supernova has yet been associated with an ultra-long-duration γ-ray burst. here we report that a supernova (sn 2011kl) was associated with the ultra-long-duration γ-ray burst grb 111209a, at a redshift z of 0.677. this supernova is more than three times more luminous than type ic supernovae associated with long-duration γ-ray bursts, and its spectrum is distinctly different. the slope of the continuum resembles those of super-luminous supernovae, but extends further down into the rest-frame ultraviolet implying a low metal content. the light curve evolves much more rapidly than those of super-luminous supernovae. this combination of high luminosity and low metal-line opacity cannot be reconciled with typical type ic supernovae, but can be reproduced by a model where extra energy is injected by a strongly magnetized neutron star (a magnetar), which has also been proposed as the explanation for super-luminous supernovae. | a very luminous magnetar-powered supernova associated with an ultra-long γ-ray burst |
the wide field infrared survey telescope (wfirst) was the highest-ranked large space-based mission of the 2010 new worlds, new horizons decadal survey. it is now a nasa mission in formulation with a planned launch in the mid 2020s. a primary mission objective is to precisely constrain the nature of dark energy through multiple probes, including type ia supernovae (sn ia). here, we present the first realistic simulations of the wfirst sn survey based on current hardware specifications and using open-source tools. we simulate sn light curves and spectra as viewed by the wfirst wide-field channel (wfc) imager and integral field channel (ifc) spectrometer, respectively. we examine 11 survey strategies with different time allocations between the wfc and ifc, two of which are based upon the strategy described by the wfirst science definition team, which measures sn distances exclusively from ifc data. we propagate statistical and, crucially, systematic uncertainties to predict the dark energy task force figure of merit (fom) for each strategy. of the strategies investigated, we find the most successful to be wfc focused. however, further work in constraining systematics is required to fully optimize the use of the ifc. even without improvements to other cosmological probes, the wfirst sn survey has the potential to increase the fom by more than an order of magnitude from the current values. although the survey strategies presented here have not been fully optimized, these initial investigations are an important step in the development of the final hardware design and implementation of the wfirst mission. | simulations of the wfirst supernova survey and forecasts of cosmological constraints |
massive black holes (bhs) inhabit local galaxies, including the milky way and some dwarf galaxies. bh formation, occurring at early cosmic times, must account for the properties of bhs in today's galaxies, notably why some galaxies host a bh, and others do not. we investigate the formation, distribution and growth of bh 'seeds' by using the adaptive mesh refinement code ramses. we develop an implementation of bh formation in dense, low-metallicity environments, as advocated by models invoking the collapse of the first generation of stars, or of dense nuclear star clusters. the seed masses are computed one-by-one on-the-fly, based on the star formation rate and the stellar initial mass function. this self-consistent method to seed bhs allows us to study the distribution of bhs in a cosmological context and their evolution over cosmic time. we find that all high-mass galaxies tend to host a bh, whereas low-mass counterparts have a lower probability of hosting a bh. after the end of the epoch of bh formation, this probability is modulated by the growth of the galaxy. the simulated bhs connect to low-redshift observational samples, and span a similar range in accretion properties as lyman-break analogs. the growth of bhs in low-mass galaxies is stunted by strong supernova (sn) feedback. the properties of bhs in dwarf galaxies thus remain a testbed for bh formation. simulations with strong sn feedback, which is able to quench bh accretion in shallow potential wells, produce galaxies and bhs in better agreement with observational constraints. | blossoms from black hole seeds: properties and early growth regulated by supernova feedback |
gw190521 challenges our understanding of the late-stage evolution of massive stars and the effects of the pair instability in particular. we discuss the possibility that stars at low or zero metallicity could retain most of their hydrogen envelope until the pre-supernova stage, avoid the pulsational pair-instability regime, and produce a black hole with a mass in the mass gap by fallback. we present a series of new stellar evolution models at zero and low metallicity computed with the geneva and mesa stellar evolution codes and compare to existing grids of models. models with a metallicity in the range 0-0.0004 have three properties that favour higher black hole (bh) masses. these are (i) lower mass-loss rates during the post main sequence phase, (ii) a more compact star disfavouring binary interaction, and (iii) possible h-he shell interactions which lower the co core mass. we conclude that it is possible that gw190521 may be the merger of black holes produced directly by massive stars from the first stellar generations. our models indicate bh masses up to 70-75 m⊙. uncertainties related to convective mixing, mass loss, h-he shell interactions, and pair-instability pulsations may increase this limit to ~85 m⊙. | is gw190521 the merger of black holes from the first stellar generations? |
we propose a logarithmic parametrization form of energy density for the scalar field dark energy in the framework of the standard theory of gravity, which supports the necessary transition from the decelerated to the accelerated behavior of the universe. the model under consideration is constrained by available observational data, including cosmic chronometers data-sets (cc), baryonic acoustic oscillation (bao) data-sets, and supernovae (sn) data-sets, consisting of only two parameters α and β . the combined cc+bao+sn data-sets yields a transition redshift of ztr=0 .79-0.02+0.02 , where the model exhibits signature-flipping and is consistent with recent observations. for the combined data-sets, the present value of the deceleration parameter is calculated to be q0=-0 .43-0.06+0.06 . furthermore, the analysis yields constraints on both the parameter density value for matter and the present value of the hubble parameter, with values of ωm 0=0 .25849-0.00025+0.00026 and h0=67 .79-0.59+0.59 km/s/mpc, respectively, consistent with the results obtained from planck 2018. finally, the study investigates how the mass of a black hole evolves over time in a universe with both matter and dark energy. it reveals that the black hole mass increases initially but stops increasing as dark energy dominates. | observational constraints on a logarithmic scalar field dark energy model and black hole mass evolution in the universe |
we present a model of early modified gravity (emg) consisting in a scalar field σ with a nonminimal coupling to the ricci curvature of the type mpl2+ξ σ2 plus a cosmological constant and a small effective mass and demonstrate its ability to alleviate the h0 tension while providing a good fit to cosmic microwave background (cmb) anisotropies and baryon acoustic oscillations (bao) data. in this model the scalar field, frozen deep in the radiation era, grows around the redshift of matter-radiation equality because of the coupling to nonrelativistic matter. the small effective mass, which we consider here as induced by a quartic potential, then damps the scalar field into coherent oscillations around its minimum at σ =0 , leading to a weaker gravitational strength at early times and naturally recovering the consistency with laboratory and solar system tests of gravity. we analyze the capability of emg with positive ξ to fit current cosmological observations and compare our results to the case without an effective mass and to the popular early dark energy models with ξ =0 . we show that emg with a quartic coupling of the order of λ ∼o (ev4/mpl4) can substantially alleviate the h0 tension also when the full shape of the matter power spectrum is included in the fit in addition to cmb and supernovae (sn) data. | early modified gravity in light of the h0 tension and lss data |
we present an analysis of the final data release of the carnegie supernova project i, focusing on the absolute calibration of the luminosity-decline rate relation for type ia supernovae (sne ia) using new intrinsic color relations with respect to the color-stretch parameter, sbv , enabling improved dust extinction corrections. we investigate to what degree the so-called fast-declining sne ia can be used to determine accurate extragalactic distances. we estimate the intrinsic scatter in the luminosity-decline rate relation and find it ranges from ±0.13 mag to ±0.18 mag with no obvious dependence on wavelength. using the cepheid variable star data from the sh0es project, the sn ia distance scale is calibrated and the hubble constant is estimated using our optical and near-infrared sample, and these results are compared to those determined exclusively from a near-infrared subsample. the systematic effect of the supernova’s host galaxy mass is investigated as a function of wavelength and is found to decrease toward redder wavelengths, suggesting this effect may be due to dust properties of the host. using estimates of the dust extinction derived from optical and near-infrared wavelengths and applying these to the h band, we derive a hubble constant {h}0=73.2+/-2.3 {km} {{{s}}}-1 {mpc}}-1, whereas using a simple b - v color correction applied to the b band yields {h}0=72.7+/-2.1 {km} {{{s}}}-1 {mpc}}-1. photometry of two calibrating sne ia from the csp-ii sample, sn 2012ht and sn 2015f, is presented and used to improve the calibration of the sn ia distance ladder. | the carnegie supernova project: absolute calibration and the hubble constant |
we perform a comprehensive analysis of the most common early- and late-universe solutions to the h0 , ly -α , and s8 discrepancies. when considered on their own, massive neutrinos provide a natural solution to the s8 discrepancy at the expense of increasing the h0 tension. if all extensions are considered simultaneously, the best-fit solution has a neutrino mass sum of ∼0.4 ev , a dark energy equation of state close to that of a cosmological constant, and no additional relativistic degrees of freedom (d.o.f). however, the h0 tension, while weakened, remains unresolved. motivated by this result, we perform a nonparametric reconstruction of the evolution of the dark energy fluid density (allowing for negative energy densities), together with massive neutrinos. when all data sets are included, there exists a residual ∼1.9 σ tension with h0. if this residual tension remains in the future, it will indicate that it is not possible to solve the h0 tension solely with a modification of the late-universe dynamics within standard general relativity. however, we do find that it is possible to resolve the tension if either galaxy baryon acoustic oscillation (bao) or joint light-curve analysis supernovae data are omitted. we find that negative dark energy densities are favored near redshift z ∼2.35 when including the ly -α bao measurement (at ∼2 σ ). this behavior may point to a negative curvature, but it is most likely indicative of systematics or at least an underestimated covariance matrix. quite remarkably, we find that in the extended cosmologies considered in this work, the neutrino mass sum is always close to 0.4 ev regardless of the choice of external data sets, as long as the h0 tension is solved or significantly decreased. | implications of an extended dark energy cosmology with massive neutrinos for cosmological tensions |
we analyse the demographics of black holes (bhs) in the large-volume cosmological hydrodynamical simulation horizon-agn. this simulation statistically models how much gas is accreted on to bhs, traces the energy deposited into their environment and, consequently, the back-reaction of the ambient medium on bh growth. the synthetic bhs reproduce a variety of observational constraints such as the redshift evolution of the bh mass density and the mass function. strong self-regulation via agn feedback, weak supernova feedback, and unresolved internal processes result in a tight bh-galaxy mass correlation. starting at z ∼ 2, tidal stripping creates a small population of bhs over-massive with respect to the halo. the fraction of galaxies hosting a central bh or an agn increases with stellar mass. the agn fraction agrees better with multi-wavelength studies, than single-wavelength ones, unless obscuration is taken into account. the most massive haloes present bh multiplicity, with additional bhs gained by ongoing or past mergers. in some cases, both a central and an off-centre agn shine concurrently, producing a dual agn. this dual agn population dwindles with decreasing redshift, as found in observations. specific accretion rate and eddington ratio distributions are in good agreement with observational estimates. the bh population is dominated in turn by fast, slow, and very slow accretors, with transitions occurring at z = 3 and z = 2, respectively. | the cosmic evolution of massive black holes in the horizon-agn simulation |
we present a numerical parameter survey of sub-chandrasekhar mass white dwarf (wd) explosions. carbon-oxygen wds accreting a helium shell have the potential to explode in the sub-chandrasekhar mass regime. previous studies have shown how the ignition of a helium shell can either directly ignite the wd at the core-shell interface or propagate a shock wave into the the core causing a central ignition. we examine the explosions of wds from 0.6 to 1.2 m ⊙ with helium shells of 0.01, 0.05, and 0.08 m ⊙. distinct observational signatures of sub-chandrasekhar mass wd explosions are predicted for two categories of shell size. thicker-shell models show an early time flux excess, which is caused by the presence of radioactive material in the ashes of the helium shell, and red colors due to these ashes creating significant line blanketing in the uv through the blue portion of the spectrum. thin shell models reproduce several typical type ia supernova signatures. we identify a relationship between si ii velocity and luminosity that, for the first time, identifies a subclass of observed supernovae that are consistent with these models. this subclass is further delineated by the absence of carbon in their atmospheres. we suggest that the proposed difference in the ratio of selective to total extinction between the high velocity and normal velocity type ia supernovae is not due to differences in the properties of the dust around these events, but is rather an artifact of applying a single extinction correction to two intrinsically different populations of supernovae. | observational predictions for sub-chandrasekhar mass explosions: further evidence for multiple progenitor systems for type ia supernovae |
we report a degeneracy between the gravitational-wave signals from quasicircular precessing black-hole mergers and those from extremely eccentric mergers, namely, head-on collisions. performing model selection on numerically simulated signals of head-on collisions using models for quasicircular binaries, we find that, for signal-to-noise ratios of 15 and 25, typical of advanced ligo observations, head-on mergers with respective total masses of m ∈(125 ,300 )m⊙ and m ∈(200 ,440 )m⊙ would be identified as precessing quasicircular intermediate-mass black-hole binaries located at a much larger distance. ruling out the head-on scenario would require us to perform model selection using currently nonexistent waveform models for head-on collisions, together with the application of astrophysically motivated priors on the (rare) occurrence of those events. we show that in situations where standard parameter inference of compact binaries may report component masses inside (outside) the pair-instability supernova gap, the true object may be a head-on merger with masses outside (inside) this gap. we briefly discuss the potential implications of these findings for gw190521, which we analyze in detail in j. calderón bustillo et al., phys. rev. lett. 126, 081101 (2021), 10.1103/physrevlett.126.081101. | confusing head-on collisions with precessing intermediate-mass binary black hole mergers |
in this paper we present an extensive analysis of the gw190521 gravitational wave event with the current (fourth) generation of phenomenological waveform models for binary black hole coalescences. gw190521 stands out from other events since only a few wave cycles are observable. this leads to a number of challenges, one being that such short signals are prone to not resolving approximate waveform degeneracies, which may result in multimodal posterior distributions. the family of waveform models we use includes a new fast time-domain model (imrphenomtphm), which allows us to extensively test different priors and robustness with respect to variations in the waveform model, including the content of spherical harmonic modes. we clarify some issues raised in a recent paper, nitz & capano, associated with possible support for a high-mass-ratio source, but confirm their finding of a multimodal posterior distribution, albeit with important differences in the statistical significance of the peaks. in particular, we find that the support for both masses being outside the pair instability supernova mass gap, and the support for an intermediate-mass-ratio binary are drastically reduced with respect to what nitz & capano found. we also provide updated probabilities for associating gw190521 to the potential electromagnetic counterpart from the zwicky transient facility (ztf) graham et al. | a detailed analysis of gw190521 with phenomenological waveform models |
gw170817 is the first detected gravitational wave source from a neutron star merger. we present the japanese collaboration for gravitational-wave electro-magnetic (j-gem) follow-up observations of sss17a, an electromagnetic counterpart of gw170817. sss17a shows a 2.5 mag decline in the z band during the period between 1.7 and 7.7 d after the merger. such a rapid decline is not comparable with supernovae light curves at any epoch. the color of sss17a also evolves rapidly and becomes redder during later epochs: the z - h color has changed by approximately 2.5 mag during the period between 0.7 and 7.7 d. the rapid evolutions of both the color and the optical brightness are consistent with the expected properties of a kilonova that is powered by the radioactive decay of newly synthesized r-process nuclei. kilonova models with lanthanide elements can reproduce the aforementioned observed properties well, which suggests that r-process nucleosynthesis beyond the second peak takes place in sss17a. however, the absolute magnitude of sss17a is brighter than the expected brightness of the kilonova models with an ejecta mass of 0.01 m⊙, which suggests a more intense mass ejection (∼0.03 m⊙) or possibly an additional energy source. | j-gem observations of an electromagnetic counterpart to the neutron star merger gw170817 |
we reanalyze the cepheid data used to infer the value of the hubble constant h0 by calibrating type ia supernovae. we do not enforce a universal value of the empirical cepheid calibration parameters rw (cepheid wesenheit color-luminosity parameter) and mhw (cepheid wesenheit h-band absolute magnitude). instead, we allow for variation of either of these parameters for each individual galaxy. we also consider the case where these parameters have two universal values: one for low galactic distances d <dc and one for high galactic distances d >dc, where dc is a critical transition distance. we find hints for a 3 σ level mismatch between the low and high galactic distance parameter values. we then use model selection criteria [akaike information criterion (aic) and bayesian information criterion (bic)], which penalize models with large numbers of parameters, to compare and rank the following types of rw and mhw parameter variations: base models: universal values for rw and mhw (no parameter variation), i: individual fitted galactic rw with one universal fitted mhw, ii: one universal fixed rw with individual fitted galactic mhw, iii: one universal fitted rw with individual fitted galactic mhw, iv: two universal fitted rw (near and far) with one universal fitted mhw, v: one universal fitted rw with two universal fitted mhw (near and far), and vi: two universal fitted rw (near and far) with two universal fitted mhw (near and far). we find that the aic and bic model selection criteria consistently favor model iv instead of the commonly used base model, where no variation is allowed for the cepheid empirical parameters. the best-fit value of the snia absolute magnitude mb and of h0 implied by the favored model iv is consistent with the inverse distance ladder calibration based on the cosmic microwave background sound horizon h0=67.4 ±0.5 km s-1 mpc-1 . thus, in the context of the favored model iv the hubble crisis is not present. this model may imply the presence of a fundamental physics transition taking place at a time more recent than 100 m y r ago. | hubble tension or a transition of the cepheid snia calibrator parameters? |
the most massive and shortest-lived stars dominate the chemical evolution of the pre-galactic era. on the basis of numerical simulations, it has long been speculated that the mass of such first-generation stars was up to several hundred solar masses1-4. the very massive first-generation stars with a mass range from 140 to 260 solar masses are predicted to enrich the early interstellar medium through pair-instability supernovae (pisne)5. decades of observational efforts, however, have not been able to uniquely identify the imprints of such very massive stars on the most metal-poor stars in the milky way6,7. here we report the chemical composition of a very metal-poor (vmp) star with extremely low sodium and cobalt abundances. the sodium with respect to iron in this star is more than two orders of magnitude lower than that of the sun. this star exhibits very large abundance variance between the odd- and even-charge-number elements, such as sodium/magnesium and cobalt/nickel. such peculiar odd-even effect, along with deficiencies of sodium and α elements, are consistent with the prediction of primordial pair-instability supernova (pisn) from stars more massive than 140 solar masses. this provides a clear chemical signature indicating the existence of very massive stars in the early universe. | a metal-poor star with abundances from a pair-instability supernova |
we introduce supernnova, an open-source supernova photometric classification framework that leverages recent advances in deep neural networks. our core algorithm is a recurrent neural network (rnn) that is trained to classify light curves using only photometric information. additional information such as host-galaxy redshift can be incorporated to improve performance. we evaluate our framework using realistic supernova simulations that include survey detection. we show that our method, for the type ia versus non-ia supernova classification problem, reaches accuracies greater than 96.92 ± 0.09 without any redshift information and up to 99.55 ± 0.06 when redshift, either photometric or spectroscopic, is available. further, we show that our method attains unprecedented performance for the classification of incomplete light curves, reaching accuracies >86.4 ± 0.1 (>93.5 ± 0.8) without host-galaxy redshift (with redshift information) 2 d before maximum light. in contrast with previous methods, there is no need for time-consuming feature engineering and we show that our method scales to very large data sets with a modest computing budget. in addition, we investigate often neglected pitfalls of machine learning algorithms. we show that commonly used algorithms suffer from poor calibration and overconfidence on out-of-distribution samples when applied to supernova data. we devise extensive tests to estimate the robustness of classifiers and cast the learning procedure under a bayesian light, demonstrating a much better handling of uncertainties. we study the benefits of bayesian rnns for sn ia cosmology. our code is open sourced and available on github1. | supernnova: an open-source framework for bayesian, neural network-based supernova classification |
the determination of the hubble constant h0 from the cosmic microwave background by the planck collaboration (n. aghanim et al., arxiv:1807.06209) is in tension at 4.2 σ with respect to the local determination of h0 by the sh0es collaboration [m. j. reid et al., astrophys. j. lett. 886, l27 (2019) https://doi.org/10.3847/2041-8213/ab552d]. here we improve upon the local determination, which fixes the deceleration parameter to the standard λ cdm model value of q0=-0.55 , that is, uses information from observations beyond the local universe. first, we derive the effective calibration prior on the absolute magnitude mb of type ia supernovae, which can be used in cosmological analyses in order to avoid the double counting of low-redshift supernovae. we find mb=-19.2334 ±0.0404 mag. then we use the above mb prior in order to obtain a determination of the local h0 which uses only local observations and assumes only the cosmological principle, that is, large-scale homogeneity and isotropy. this is achieved by adopting an uninformative flat prior for q0 in the cosmographic expansion of the luminosity distance. we use the latest pantheon sample and find h0=75.35 ±1.68 kms-1mpc-1 , which features a 2.2% uncertainty, close to the 1.9% error obtained by the sh0es collaboration. our determination is at the higher tension of 4.5 σ with the latest results from the planck collaboration that assume the λ cdm model. furthermore, we also constrain the deceleration parameter to q0=-1.08 ±0.29 , which disagrees with the planck collaboration at the 1.9 σ level. these estimations only use supernovae in the redshift range 0.023 ≤z ≤0.15 . | local determination of the hubble constant and the deceleration parameter |
we use planck 2018 data to constrain the simplest models of scalar-tensor theories characterized by a coupling to the ricci scalar of the type f(σ) r with f(σ) = npl2 + ξ σ2. we update our results with previous planck and bao data releases obtaining the tightest constraints to date on the coupling parameters, that is ξ < 5.5 × 10-4 for npl=0 (induced gravity or equivalently extended jordan-brans-dicke) and (npl √8 π g)-1 < 1.8 × 10-5 for ξ = -1/6 (conformal coupling), both at 95% cl. because of a modified expansion history after radiation-matter equality compared to the λcdm model, all these dynamical models accommodate a higher value for h0 and therefore alleviate the tension between planck/bao and distance-ladder measurement from sne ia data from 4.4σ at best to 2.7-3.2σ with cmb alone and 3.5-3.6σ including bao data. we show that all these results are robust to changes in the neutrino physics. in comparison to the λcdm model, partial degeneracies between neutrino physics and the coupling to the ricci scalar allow for smaller values neff ~ 2.8, 1σ lower compared to the standard neff = 3.046, and relax the upper limit on the neutrino mass up to 40%. | scalar-tensor theories of gravity, neutrino physics, and the h0 tension |
we revisit a singlet majoron model in which neutrino masses arise from the spontaneous violation of lepton number. if the majoron obtains a mass of order mev, it can play the role of dark matter. we discuss constraints on the couplings of the massive majoron with masses of order mev to neutrinos from supernova data. in the dense supernova core, majoron-emitting neutrino annihilations are allowed and can change the signal of a supernova. based on the observation of sn1987a, we exclude a large range of couplings from the luminosity and the deleptonization arguments, taking the effect of the background medium into account. if the majoron mass does not exceed the q-value of the experiment, the neutrino-majoron couplings allow for neutrinoless double beta decay with majoron emission. we derive constraints on the couplings for a majoron mass of order mev based on the phase space suppression and the diminishing signal-to-background ratio due to the majoron mass. the combination of constraints from astrophysics and laboratory experiments excludes a large range of neutrino-majoron couplings in the mass range of interest for majoron dark matter, where they complement existing cosmological bounds from dark matter stability and the effects of a decaying majoron on the cosmic microwave background anisotropy spectrum. | massive majorons and constraints on the majoron-neutrino coupling |
we revisit the physics of neutrino magnetic moments, focusing in particular on the case where the right-handed, or sterile, neutrinos are heavier (up to several mev) than the left-handed standard model neutrinos. the discussion is centered around the idea of detecting an upscattering event mediated by a transition magnetic moment in a neutrino or dark matter experiment. considering neutrinos from all known sources, as well as including all available data from xenon1t and borexino, we derive the strongest up-to-date exclusion limits on the active-to-sterile neutrino transition magnetic moment. we then study complementary constraints from astrophysics and cosmology, performing, in particular, a thorough analysis of bbn . we find that these data sets scrutinize most of the relevant parameter space. explaining the xenon1t excess with transition magnetic moments is marginally possible if very conservative assumptions are adopted regarding the supernova 1987 a and cmb constraints. finally, we discuss model-building challenges that arise in scenarios that feature large magnetic moments while keeping neutrino masses well below 1 ev. we present a successful ultraviolet-complete model of this type based on tev-scale leptoquarks, establishing links with muon magnetic moment, b physics anomalies, and collider searches at the lhc. | the neutrino magnetic moment portal: cosmology, astrophysics, and direct detection |
we provide a set of stellar evolution and nucleosynthesis calculations that applies established physics assumptions simultaneously to low- and intermediate-mass and massive star models. our goal is to provide an internally consistent and comprehensive nuclear production and yield database for applications in areas such as presolar grain studies. our non-rotating models assume convective boundary mixing (cbm) where it has been adopted before. we include 8 (12) initial masses for z = 0.01 (0.02). models are followed either until the end of the asymptotic giant branch phase or the end of si burning, complemented by simple analytic core-collapse supernova (sn) models with two options for fallback and shock velocities. the explosions show which pre-sn yields will most strongly be effected by the explosive nucleosynthesis. we discuss how these two explosion parameters impact the light elements and the s and p process. for low- and intermediate-mass models, our stellar yields from h to bi include the effect of cbm at the he-intershell boundaries and the stellar evolution feedback of the mixing process that produces the {}13{{c}} pocket. all post-processing nucleosynthesis calculations use the same nuclear reaction rate network and nuclear physics input. we provide a discussion of the nuclear production across the entire mass range organized by element group. the entirety of our stellar nucleosynthesis profile and time evolution output are available electronically, and tools to explore the data on the nugrid vospace hosted by the canadian astronomical data centre are introduced. | nugrid stellar data set. i.stellar yields from h to bi for stars with metallicities z = 0.02 and z = 0.01 |
we study observational constraints on the nonmetricity f (q )-gravity which reproduces an exact λ cdm background expansion history while modifying the evolution of linear perturbations. to this purpose we use cosmic microwave background (cmb) radiation, baryonic acoustic oscillations (bao), redshift-space distortions (rsd), supernovae type ia (snia), galaxy clustering (gc) and weak gravitational lensing (wl) measurements. we set stringent constraints on the parameter of the model controlling the modifications to the gravitational interaction at linear perturbation level. we find the model to be statistically preferred by data over the λ cdm according to the χ2 and deviance information criterion statistics for the combination with cmb, bao, rsd and snia. this is mostly associated to a better fit to the low-ℓ tail of cmb temperature anisotropies. | can f (q ) gravity challenge λ cdm ? |
to uniformly determine the properties of supernova remnants (snrs) at high energies, we have developed the first systematic survey at energies from 1 to 100 gev using data from the fermi large area telescope (lat). based on the spatial overlap of sources detected at gev energies with snrs known from radio surveys, we classify 30 sources as likely gev snrs. we also report 14 marginal associations and 245 flux upper limits. a mock catalog in which the positions of known remnants are scrambled in galactic longitude allows us to determine an upper limit of 22% on the number of gev candidates falsely identified as snrs. we have also developed a method to estimate spectral and spatial systematic errors arising from the diffuse interstellar emission model, a key component of all galactic fermi lat analyses. by studying remnants uniformly in aggregate, we measure the gev properties common to these objects and provide a crucial context for the detailed modeling of individual snrs. combining our gev results with multiwavelength (mw) data, including radio, x-ray, and tev, we demonstrate the need for improvements to previously sufficient, simple models describing the gev and radio emission from these objects. we model the gev and mw emission from snrs in aggregate to constrain their maximal contribution to observed galactic cosmic rays. | the first fermi lat supernova remnant catalog |
the inner ~200 pc region of the galaxy contains a 4 million m⊙ supermassive black hole (smbh), significant quantities of molecular gas, and star formation and cosmic-ray energy densities that are roughly two orders of magnitude higher than the corresponding levels in the galactic disk. at a distance of only 8.2 kpc, the region presents astronomers with a unique opportunity to study a diverse range of energetic astrophysical phenomena, from stellar objects in extreme environments, to the smbh and star-formation-driven feedback processes that are known to influence the evolution of galaxies as a whole. we present a new survey of the galactic center conducted with the south african meerkat radio telescope. radio imaging offers a view that is unaffected by the large quantities of dust that obscure the region at other wavelengths, and a scene of striking complexity is revealed. we produce total-intensity and spectral-index mosaics of the region from 20 pointings (144 hr on-target in total), covering 6.5 square degrees with an angular resolution of 4″ at a central frequency of 1.28 ghz. many new features are revealed for the first time due to a combination of meerkat's high sensitivity, exceptional u, v-plane coverage, and geographical vantage point. we highlight some initial survey results, including new supernova remnant candidates, many new nonthermal filament complexes, and enhanced views of the radio arc bubble, sagittarius a, and sagittarius b regions. this project is a south african radio astronomy observatory public legacy survey, and the image products are made available with this article. | the 1.28 ghz meerkat galactic center mosaic |
models of neutrino-driven core-collapse supernova explosions have matured considerably in recent years. explosions of low-mass progenitors can routinely be simulated in 1d, 2d, and 3d. nucleosynthesis calculations indicate that these supernovae could be contributors of some lighter neutron-rich elements beyond iron. the explosion mechanism of more massive stars remains under investigation, although first 3d models of neutrino-driven explosions employing multi-group neutrino transport have become available. together with earlier 2d models and more simplified 3d simulations, these have elucidated the interplay between neutrino heating and hydrodynamic instabilities in the post-shock region that is essential for shock revival. however, some physical ingredients may still need to be added/improved before simulations can robustly explain supernova explosions over a wide range of progenitors. solutions recently suggested in the literature include uncertainties in the neutrino rates, rotation, and seed perturbations from convective shell burning. we review the implications of 3d simulations of shell burning in supernova progenitors for the `perturbations-aided neutrino-driven mechanism,' whose efficacy is illustrated by the first successful multi-group neutrino hydrodynamics simulation of an 18 solar mass progenitor with 3d initial conditions. we conclude with speculations about the impact of 3d effects on the structure of massive stars through convective boundary mixing. | the status of multi-dimensional core-collapse supernova models |
we employ robust weak gravitational lensing measurements to improve cosmological constraints from measurements of the galaxy cluster mass function and its evolution, using x-ray selected clusters detected in the rosat all-sky survey. our lensing analysis constrains the absolute mass scale of such clusters at the 8 per cent level, including both statistical and systematic uncertainties. combining it with the survey data and x-ray follow-up observations, we find a tight constraint on a combination of the mean matter density and late-time normalization of the matter power spectrum, σ8(ωm/0.3)0.17 = 0.81 ± 0.03, with marginalized, one-dimensional constraints of ωm = 0.26 ± 0.03 and σ8 = 0.83 ± 0.04. for these two parameters, this represents a factor of 2 improvement in precision with respect to previous work, primarily due to the reduced systematic uncertainty in the absolute mass calibration provided by the lensing analysis. our new results are in good agreement with constraints from cosmic microwave background (cmb) data, both wilkinson microwave anisotropy probe (wmap) and planck (plus wmap polarization), under the assumption of a flat λcdm cosmology with minimal neutrino mass. consequently, we find no evidence for non-minimal neutrino mass from the combination of cluster data with cmb, supernova and baryon acoustic oscillation measurements, regardless of which all-sky cmb data set is used (and independent of the recent claimed detection of b modes on degree scales). we also present improved constraints on models of dark energy (both constant and evolving), modifications of gravity, and primordial non-gaussianity. assuming flatness, the constraints for a constant dark energy equation of state from the cluster data alone are at the 15 per cent level, improving to ∼6 per cent when the cluster data are combined with other leading probes. | weighing the giants - iv. cosmology and neutrino mass |
context. spectroscopic surveys of massive galaxy clusters reveal the properties of faint background galaxies thanks to the magnification provided by strong gravitational lensing.aims: we present a systematic analysis of integral-field-spectroscopy observations of 12 massive clusters, conducted with the multi unit spectroscopic explorer (muse). all data were taken under very good seeing conditions (∼0″.6) in effective exposure times between two and 15 h per pointing, for a total of 125 h. our observations cover a total solid angle of ∼23 arcmin2 in the direction of clusters, many of which were previously studied by the massive clusters survey, frontier fields (ffs), grism lens-amplified survey from space and cluster lensing and supernova survey with hubble programmes. the achieved emission line detection limit at 5σ for a point source varies between (0.77-1.5) × 10-18 erg s-1 cm-2 at 7000 å.methods: we present our developed strategy to reduce these observational data, detect continuum sources and line emitters in the datacubes, and determine their redshifts. we constructed robust mass models for each cluster to further confirm our redshift measurements using strong-lensing constraints, and identified a total of 312 strongly lensed sources producing 939 multiple images.results: the final redshift catalogues contain more than 3300 robust redshifts, of which 40% are for cluster members and ∼30% are for lensed lyman-α emitters. fourteen percent of all sources are line emitters that are not seen in the available hst images, even at the depth of the ffs (∼29 ab). we find that the magnification distribution of the lensed sources in the high-magnification regime (μ = 2-25) follows the theoretical expectation of n(z) ∝ μ-2. the quality of this dataset, number of lensed sources, and number of strong-lensing constraints enables detailed studies of the physical properties of both the lensing cluster and the background galaxies. the full data products from this work, including the datacubes, catalogues, extracted spectra, ancillary images, and mass models, are made available to the community. the dataset and full tables a.1. and a.2 are only available at the cds via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/cat/j/a+a/646/a83 | an atlas of muse observations towards twelve massive lensing clusters |
a universal mechanism may be responsible for several unresolved cosmic conundra. the sudden drop in the pressure of relativistic matter at w± ∕z0 decoupling, the quark-hadron transition and e+e- annihilation enhances the probability of primordial black hole (pbh) formation in the early universe. assuming the amplitude of the primordial curvature fluctuations is approximately scale-invariant, this implies a multi-modal pbh mass spectrum with peaks at 10-6 , 1, 30, and 106m⊙ . this suggests a unified pbh scenario which naturally explains the dark matter and recent microlensing observations, the ligo/virgo black hole mergers, the correlations in the cosmic infrared and x-ray backgrounds, and the origin of the supermassive black holes in galactic nuclei at high redshift. a distinctive prediction of our model is that ligo/virgo should observe black hole mergers in the mass gaps between 2 and 5m⊙ (where no stellar remnants are expected) and above 65m⊙ (where pair-instability supernovae occur) and low-mass-ratios in between. therefore the recent detection of events gw190425, gw190814 and gw190521 with these features is striking confirmation of our prediction and may indicate a primordial origin for the black holes. in this case, the exponential sensitivity of the pbh abundance to the equation of state would offer a unique probe of the qcd phase transition. the detection of pbhs would also offer a novel way to probe the existence of new particles or phase transitions with energy between 1 mev and 1010 gev. | cosmic conundra explained by thermal history and primordial black holes |
a century ago, nuclear physics entered astrophysics, giving birth to a new field of science referred to as "nuclear astrophysics". with time, it developed at an impressive pace into a vastly inter- and multidisciplinary field bringing into its wake not only astronomy and cosmology, but also many other sub-fields of physics, especially particle, solid-state and computational physics, as well as chemistry, geology and even biology. the present astronuclear physics review focusses primarily on the facets of nuclear physics that are of relevance to astronomy and astrophysics, the theoretical aspects being of special concern here. the observational aspects of astronomy and astrophysics that may have some connection to nuclear physics are only broadly reviewed, mainly through the provision of recent relevant references. multi-messenger astronomy has developed most remarkably during the last decades, with often direct implications for nuclear astrophysics. the electromagnetic view of the components of the universe has improved dramatically at all wavelengths, from the γ-ray to the radio domains, providing important new information on the big bang and the properties of stars. neutrino astronomy has made giant steps forward. in particular, the famed "solar neutrino problem" is now behind us. the long-sought gravitational waves have at last been detected, with direct relevance namely to the merger of compact stars. the composition of galactic cosmic rays and stellar/solar energetic particles is better known than ever, providing constrains on the gcr physics. on the stellar modeling side, we broadly brush the progress that has been made based on new observations, and even more so on the spectacular increase in computer capabilities. we briefly outline recent advances regarding the quiescent evolution of stars, as well as the eventual catastrophic supernova explosion of certain classes of them. in spite of significant improvements in the simulations, many long-standing problems still await solid solutions, particularly regarding the details and robustness of explosion simulations. in fact, new questions are continuously emerging, and new facts may endanger old ideas. the lion's share of this review concerns the nuclear physics phenomena that may be at work in astrophysical conditions, with a strong focus on theory. exceptionally large varieties of nuclei have to be dealt with, ranging from the lightest to the heaviest ones, from the valley of nuclear stability all the way to the proton and neutron drip lines. an additional serious difficulty comes from the fact that the nuclei are immersed in highly unusual environments which may have a significant impact on their static properties, the diversity of their transmutation modes, some of which not being observable in the laboratory, and on the probabilities of these modes. the description of nuclei as individual entities has even to be replaced by the construction of an equation of state at high enough temperatures and/or densities prevailing in the cores of exploding stars and in compact objects (neutron stars). the determination of a huge body of thermonuclear reaction cross sections is an especially challenging task, having to face the "world of almost no event" due to the smallness of the relative energies of charged-particle induced reactions relative to the coulomb barriers, and/or the "world of exoticism", as highly unstable nuclei are involved in several nucleosynthesis processes. the synthesis of the nuclides heavier than iron is briefly reviewed. neutron capture mechanisms range from the s-process for the production of the stable nuclides located at the bottom of the valley of stability to the r-process responsible for the synthesis of the neutron-rich isobars. the origin of the neutron-deficient isobars observed in the sos is attributed to the p-process. emphasis is put on the astrophysics and nuclear physics uncertainties affecting the modeling of these nucleosynthesis mechanisms. | astronuclear physics: a tale of the atomic nuclei in the skies |
it is well-known that in addition to the standard lma solution to solar anomaly, there is another solution called lma-dark which requires non-standard interactions (nsi) with effective couplings as large as the fermi coupling. although this solution satisfies all the bounds from various neutrino oscillation observations and even provides a better fit to low energy solar neutrino spectrum, it is not as popular as the lma solution mainly because no model compatible with the existing bounds has been so far constructed to give rise to this solution. we introduce a model that provides a foundation for such large nsi with strength and flavor structure required for the lma-dark solution. this model is based on a new u(1) ‧ gauge interaction with a gauge boson of mass ∼ 10 mev under which quarks as well as the second and third generations of leptons are charged. we show that observable effects can appear in the spectrum of supernova and high energy cosmic neutrinos. our model predicts a new contribution to the muon magnetic dipole moment and new rare meson decay modes. | a model for large non-standard interactions of neutrinos leading to the lma-dark solution |
we present results from a comprehensive lensing analysis in hubble space telescope (hst) data of the complete cluster lensing and supernova survey with hubble cluster sample. we identify previously undiscovered multiple images, allowing improved or first constraints on the cluster inner mass distributions and profiles. we combine these strong lensing constraints with weak lensing shape measurements within the hst field of view (fov) to jointly constrain the mass distributions. the analysis is performed in two different common parameterizations (one adopts light-traces-mass for both galaxies and dark matter while the other adopts an analytical, elliptical navarro-frenk-white form for the dark matter) to provide a better assessment of the underlying systematics—which is most important for deep, cluster-lensing surveys, especially when studying magnified high-redshift objects. we find that the typical (median), relative systematic differences throughout the central fov are ~40% in the (dimensionless) mass density, κ, and ~20% in the magnification, μ. we show maps of these differences for each cluster, as well as the mass distributions, critical curves, and two-dimensional (2d)-integrated mass profiles. for the einstein radii (zs = 2) we find that all typically agree within 10% between the two models, and einstein masses agree, typically, within ~15%. at larger radii, the total projected, 2d-integrated mass profiles of the two models, within r ~ 2', differ by ~30%. stacking the surface-density profiles of the sample from the two methods together, we obtain an average slope of dlog (σ)/dlog (r) ~ -0.64 ± 0.1, in the radial range [5350] kpc. last, we also characterize the behavior of the average magnification, surface density, and shear differences between the two models as a function of both the radius from the center and the best-fit values of these quantities. all mass models and magnification maps are made publicly available for the community. | hubble space telescope combined strong and weak lensing analysis of the clash sample: mass and magnification models and systematic uncertainties |
we scrutinize the hypothesis that gauge singlet fermions—sterile neutrinos—interact with standard model particles through the transition magnetic moment portal. these interactions lead to the production of sterile neutrinos in supernovae followed by their decay into photons and active neutrinos which can be detected at γ -ray telescopes and neutrino detectors, respectively. we find that the nonobservation of active neutrinos and photons from sterile-neutrino decay associated to sn1987a yields the strongest constraints to date on magnetic-moment-coupled sterile neutrinos if their masses are inside a 0.1-100 mev window. assuming a near-future galactic supernova explosion, we estimate the sensitivity of several present and near-future experiments, including fermi-lat, e-astrogam, dune, and hyper-kamiokande, to magnetic-moment-coupled sterile neutrinos. we also study the diffuse photon and neutrino fluxes produced in the decay of magnetic-moment coupled sterile neutrinos produced in all past supernova explosions and find that the absence of these decay daughters yields the strongest constraints to date for sterile neutrino masses inside a 1-100 kev window. | neutrino magnetic moment portal and supernovae: new constraints and multimessenger opportunities |
context. gravitational wave (gw) astronomy has rapidly reached maturity, becoming a fundamental observing window for modern astrophysics. the coalescences of a few tens of black hole (bh) binaries have been detected, while the number of events possibly including a neutron star (ns) is still limited to a few. on 2019 august 14, the ligo and virgo interferometers detected a high-significance event labelled s190814bv. a preliminary analysis of the gw data suggests that the event was likely due to the merger of a compact binary system formed by a bh and a ns.aims: in this paper, we present our extensive search campaign aimed at uncovering the potential optical and near infrared electromagnetic counterpart of s190814bv. we found no convincing electromagnetic counterpart in our data. we therefore use our non-detection to place limits on the properties of the putative outflows that could have been produced by the binary during and after the merger.methods: thanks to the three-detector observation of s190814bv, and given the characteristics of the signal, the ligo and virgo collaborations delivered a relatively narrow localisation in low latency - a 50% (90%) credible area of 5 deg2 (23 deg2) - despite the relatively large distance of 267 ± 52 mpc. electromagnetic counterparts of gravitational wave sources at the very large telescope collaboration members carried out an intensive multi-epoch, multi-instrument observational campaign to identify the possible optical and near infrared counterpart of the event. in addition, the atlas, goto, grawita-vst, pan-starrs, and vinrouge projects also carried out a search on this event. in this paper, we describe the combined observational campaign of these groups.results: our observations allow us to place limits on the presence of any counterpart and discuss the implications for the kilonova (kn), which was possibly generated by this ns-bh merger, and for the strategy of future searches. the typical depth of our wide-field observations, which cover most of the projected sky localisation probability (up to 99.8%, depending on the night and filter considered), is r ∼ 22 (resp. k ∼ 21) in the optical (resp. near infrared). we reach deeper limits in a subset of our galaxy-targeted observations, which cover a total ∼50% of the galaxy-mass-weighted localisation probability. altogether, our observations allow us to exclude a kn with large ejecta mass m ≳ 0.1 m⊙ to a high (> 90%) confidence, and we can exclude much smaller masses in a sub-sample of our observations. this disfavours the tidal disruption of the neutron star during the merger.conclusions: despite the sensitive instruments involved in the campaign, given the distance of s190814bv, we could not reach sufficiently deep limits to constrain a kn comparable in luminosity to at 2017gfo on a large fraction of the localisation probability. this suggests that future (likely common) events at a few hundred megaparsecs will be detected only by large facilities with both a high sensitivity and large field of view. galaxy-targeted observations can reach the needed depth over a relevant portion of the localisation probability with a smaller investment of resources, but the number of galaxies to be targeted in order to get a fairly complete coverage is large, even in the case of a localisation as good as that of this event. full table 3 is only available at the cds via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/cat/j/a+a/643/a113 | observational constraints on the optical and near-infrared emission from the neutron star-black hole binary merger candidate s190814bv |
cosmic reionization is thought to be primarily fueled by the first generations of galaxies. we examine their stellar and gaseous properties, focusing on the star formation rates and the escape of ionizing photons, as a function of halo mass, redshift, and environment using the full suite of the renaissance simulations with an eye to provide better inputs to global reionization simulations. this suite probes overdense, average, and underdense regions of the universe of several hundred comoving mpc3, each yielding a sample of over 3000 halos in the mass range of 107-109.5 {m}⊙at their final redshifts of 15, 12.5, and 8, respectively. in the process, we simulate the effects of radiative and supernova feedback from 5000 to 10,000 population iii stars in each simulation. we find that halos as small as 107 {m}⊙are able to host bursty star formation due to metal-line cooling from earlier enrichment by massive population iii stars. using our large sample, we find that the galaxy-halo occupation fraction drops from unity at virial masses above 108.5 {m}⊙to ∼50% at 108 {m}⊙and ∼10% at 107 {m}⊙ , quite independent of redshift and region. their average ionizing escape fraction is ∼5% in the mass range of 108-109 {m}⊙and increases with decreasing halo mass below this range, reaching 40%-60% at 107 {m}⊙ . interestingly, we find that the escape fraction varies between 10%-20% in halos with virial masses of ∼3 × 109 {m}⊙ . taken together, our results confirm the importance of the smallest galaxies as sources of ionizing radiation contributing to the reionization of the universe. | galaxy properties and uv escape fractions during the epoch of reionization: results from the renaissance simulations |
in order to apply holography and entropy relations to the whole universe, which is a gravitational and thus nonextensive system, for consistency one should use the generalized definition for the universe horizon entropy, namely tsallis nonextensive entropy. we formulate tsallis holographic dark energy, which is a generalization of standard holographic dark energy quantified by a new dimensionless parameter δ, possessing the latter as a particular sub-case. we provide a simple differential equation for the dark energy density parameter, as well as an analytical expression for its equation-of-state parameter. in this scenario the universe exhibits the usual thermal history, namely the successive sequence of matter and dark-energy epochs, before resulting in a complete dark energy domination in the far future. additionally, the dark energy equation-of-state parameter presents a rich behavior and, according to the value of δ, it can be quintessence-like, phantom-like, or experience the phantom-divide crossing before or after the present time. finally, we confront the scenario with supernovae type ia and hubble parameter observational data, and we show that the agreement is very good, with δ preferring a value slightly larger than its standard value 1. | holographic dark energy through tsallis entropy |
solitons are observed to form in simulations of dark matter (dm) halos consisting of bosonic fields. we use the extended press-schechter formalism to compute the mass function of solitons, assuming various forms for the relationship between halo mass and soliton mass. we further provide a new calculation of the rate of soliton major mergers. solitons composed of axion dm are unstable above a critical mass, and decay to either relativistic axions or photons, depending on the values of the coupling constants. we use the computed soliton major merger rate to predict the enhanced dm decay rate due to soliton instability. for certain values of currently allowed axion parameters, the energy injection into the intergalactic medium from soliton decays to photons is comparable to or larger than the energy injection due to core collapse supernovae at $z>10$. a companion paper explores the phenomenology of such an energy injection. | soliton merger rates and enhanced axion dark matter decay |
dark matter that is capable of sufficiently heating a local region in a white dwarf will trigger runaway fusion and ignite a type ia supernova. this was originally proposed by graham et al. and used to constrain primordial black holes which transit and heat a white dwarf via dynamical friction. in this paper, we consider dark matter (dm) candidates that heat through the production of high-energy standard model (sm) particles, and show that such particles will efficiently thermalize the white dwarf medium and ignite supernovae. based on the existence of long-lived white dwarfs and the observed supernovae rate, we derive new constraints on ultraheavy dm with masses greater than 1 016 gev which produce sm particles through dm-dm annihilations, dm decays, and dm-sm scattering interactions in the stellar medium. as a concrete example, we place bounds on supersymmetric q-ball dm in parameter space complementary to terrestrial bounds. we put further constraints on dm that is captured by white dwarfs, considering the formation and self-gravitational collapse of a dm core which heats the star via decays and annihilations within the core. it is also intriguing that the dm-induced ignition discussed in this work provide an alternative mechanism of triggering supernovae from sub-chandrasekhar, nonbinary progenitors. | white dwarfs as dark matter detectors |
gamma-ray bursts (grbs), can be employed as standardized candles, extending the distance ladder beyond type ia supernovae (sne ia, z = 2.26). we standardize grbs using the three-dimensional (3d) fundamental plane relation (the dainotti relation) among the rest-frame end time of the x-ray plateau emission, its corresponding luminosity, and the peak prompt luminosity. combining sne ia and grbs, we constrain ωm = 0.299 ± 0.009 assuming a flat λ cold dark matter (λcdm) cosmology with and without correcting grbs for selection biases and redshift evolution. using a 3d optical dainotti correlation, we find this sample is as efficacious in the determination of ωm as the x-ray sample. we trimmed our grb samples to achieve tighter planes to simulate additional grbs. we determined how many grbs are needed as stand-alone probes to achieve a comparable precision on ωm to the one obtained by sne ia only. we reach the same error measurements derived using sne ia in 2011 and 2014 with 142 and 284 simulated optical grbs, respectively, considering the error bars on the variables halved. these error limits will be reached in 2038 and in 2047, respectively. using a doubled sample (obtained by future machine learning approaches allowing a light-curve reconstruction and the estimates of grb redshifts when z is unknown) compared to the current sample, with error bars halved we will reach the same precision as sne ia in 2011 and 2014, now and in 2026, respectively. if we consider the current sne precision, this will be reached with 390 optical grbs by 2054. | optical and x-ray grb fundamental planes as cosmological distance indicators |
cosmic rays with energies up to a few pev are known to be accelerated within the milky way1,2. traditionally, it has been presumed that supernova remnants were the main source of these very-high-energy cosmic rays3,4, but theoretically it is difficult to accelerate protons to pev energies5,6 and observationally there simply is no evidence of the remnants being sources of hadrons with energies above a few tens of tev7,8. one possible source of protons with those energies is the galactic centre region9. here, we report observations of 1-100 tev γ rays coming from the `cygnus cocoon'10, which is a superbubble that surrounds a region of massive star formation. these γ rays are likely produced by 10-1,000 tev freshly accelerated cosmic rays that originate from the enclosed star-forming region cyg ob2. until now it was not known that such regions could accelerate particles to these energies. the measured flux likely originates from hadronic interactions. the spectral shape and the emission profile of the cocoon changes from gev to tev energies, which reveals the transport of cosmic particles and historical activity in the superbubble. | hawc observations of the acceleration of very-high-energy cosmic rays in the cygnus cocoon |
in modified gravity the propagation of gravitational waves (gws) is in general different from that in general relativity. as a result, the luminosity distance for gws can differ from that for electromagnetic signals, and is affected both by the dark energy equation of state wde(z ) and by a function δ (z ) describing modified propagation. we show that the effect of modified propagation in general dominates over the effect of the dark energy equation of state, making it easier to distinguish a modified gravity model from λ cdm . we illustrate this using a nonlocal modification of gravity that has been shown to fit remarkably well cosmic microwave background, supernovae, baryon acoustic oscillation, and structure formation data, and we discuss the prospects for distinguishing nonlocal gravity from λ cdm with the einstein telescope. we find that, depending on the exact sensitivity, a few tens of standard sirens with measured redshift at z ∼0.4 , or a few hundreds at 1 ≲z ≲2 , could suffice. | gravitational-wave luminosity distance in modified gravity theories |
the wide field survey telescope (wfst) is a dedicated photometric surveying facility being built jointly by university of science and technology of china (ustc) and the purple mountain observatory (pmo). it is equipped with a 2.5-meter diameter primary mirror, an active optics system, and a mosaic ccd camera with 0.73 gigapixels on the primary focal plane for high-quality image capture over a 6.5-square-degree field of view. the installation of wfst near the summit of saishiteng mountain in the lenghu region is scheduled in summer of 2023, and the operation is planned to start three months later. wfst will scan the northern sky in four optical bands (u, g, r and i) at cadences from hourly/daily in the deep high-cadence survey (dhs) program, to semi-weekly in the wide field survey (wfs) program. during a photometric night, a nominal 30 s exposure in the wfs program will reach a depth of 22.27, 23.32, 22.84, and 22.31 (ab magnitudes) in these four bands, respectively, allowing for the detection of a tremendous amount of transients in the low-z universe and a systematic investigation of the variability of galactic and extragalactic objects. in the dhs program, intranight 90 s exposures as deep as 23 (u) and 24 mag (g), in combination with target of opportunity follow-ups, will provide a unique opportunity to explore energetic transients in demand for high sensitivities, including the electromagnetic counterparts of gravitational wave events, supernovae within a few hours of their explosions, tidal disruption events and fast, luminous optical transients even beyond redshift of unity. in addition, the final 6-year co-added images, anticipated to reach g ≃ 25.8 mag in wfs or 1.5 mags deeper in dhs, will be of fundamental importance to general galactic and extragalactic science. the highly uniform legacy surveys of wfst will serve as an indispensable complement to those of the vera c. rubin observatory's legacy survey of space and time (lsst) that monitors the southern sky. | science with the 2.5-meter wide field survey telescope (wfst) |
with cosmicflows-4, distances are compiled for 55,877 galaxies gathered into 38,065 groups. eight methodologies are employed, with the largest numbers coming from the correlations between the photometric and kinematic properties of spiral galaxies (tf) and elliptical galaxies (fp). supernovae that arise from degenerate progenitors (type ia sne) are an important overlapping component. smaller contributions come from distance estimates from the surface brightness fluctuations of elliptical galaxies and the luminosities and expansion rates of core-collapse supernovae (sne ii). cepheid period-luminosity relation and tip of the red giant branch observations founded on local stellar parallax measurements along with the geometric maser distance to ngc 4258 provide the absolute scaling of distances. the assembly of galaxies into groups is an important feature of the study in facilitating overlaps between methodologies. merging between multiple contributions within a methodology and between methodologies is carried out with bayesian markov chain monte carlo procedures. the final assembly of distances is compatible with a value of the hubble constant of h 0 = 74.6 km s-1 mpc-1 with the small statistical error of ±0.8 km s-1 mpc-1 but a large potential systematic error of ~3 km s-1 mpc-1. peculiar velocities can be inferred from the measured distances. the interpretation of the field of peculiar velocities is complex because of large errors on individual components and invites analyses beyond the scope of this study. | cosmicflows-4 |
recently born magnetars are promising candidates for the engines powering fast radio bursts (frbs). the focus thus far has been placed on millisecond magnetars born in rare core-collapse explosions, motivated by the star-forming dwarf host galaxy of the repeating frb 121102, which is remarkably similar to the hosts of superluminous supernovae and long gamma-ray bursts. however, long-lived magnetars may also be created in binary neutron star (bns) mergers, in the small subset of cases with a sufficiently low total mass for the remnant to avoid collapse to a black hole, or in the accretion-induced collapse (aic) of a white dwarf. a bns or aic frb channel will be characterized by distinct host galaxy and spatial offset distributions which we show are consistent with the recently reported frb 180924, localized by the australian square kilometre array pathfinder to a massive quiescent host galaxy with an offset of about 1.4 effective radii. using models calibrated to frb 121102, we make predictions for the dispersion measure, rotation measure, and persistent radio emission from magnetar frb sources born in bns mergers or aic, and show these are consistent with upper limits from frb 180924. depending on the rate of aic, and the fraction of bns mergers leaving long-lived stable magnetars, the birth rate of repeating frb sources associated with older stellar populations could be comparable to that of the core-collapse channel. we also discuss potential differences in the repetition properties of these channels, as a result of differences in the characteristic masses and magnetic fields of the magnetars. | fast radio bursts from magnetars born in binary neutron star mergers and accretion induced collapse |
early observations of supernovae (sne) indicate that enhanced mass-loss and pre-sn outbursts may occur in progenitors of many types of sne. we investigate the role of energy transport via waves driven by vigorous convection during late-stage nuclear burning of otherwise typical 15 m⊙ red supergiant sn progenitors. using mesa stellar evolution models including 1d hydrodynamics, we find that waves carry ∼107 l⊙ of power from the core to the envelope during core neon/oxygen burning in the final years before core collapse. the waves damp via shocks and radiative diffusion at the base of the hydrogen envelope, which heats up fast enough to launch a pressure wave into the overlying envelope that steepens into a weak shock near the stellar surface, causing a mild stellar outburst and ejecting a small (≲1 m⊙) amount of mass at low speed (≲50 km s-1) roughly one year before the sn. the wave heating inflates the stellar envelope but does not completely unbind it, producing a non-hydrostatic pre-sn envelope density structure different from prior expectations. in our models, wave heating is unlikely to lead to luminous type iin sne, but it may contribute to flash-ionized sne and some of the diversity seen in ii-p/ii-l sne. | pre-supernova outbursts via wave heating in massive stars - i. red supergiants |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.