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despite efforts over several decades, direct-detection experiments have not yet led to the discovery of the dark matter (dm) particle. this has led to increasing interest in alternatives to the lambda cdm (lcdm) paradigm and alternative dm scenarios (including fuzzy dm, warm dm, self-interacting dm, etc.). in many of t... | snowmass2021 cosmic frontier white paper: prospects for obtaining dark matter constraints with desi |
we study the relation between obscuration and supermassive black hole (smbh) accretion using a large sample of hard x-ray selected active galactic nuclei (agns). we find a strong decrease in the fraction of obscured sources above the eddington limit for dusty gas ( $\mathrm{log}{\lambda }_{\mathrm{edd}}\gtrsim -2$ ) co... | bass xxxvii: the role of radiative feedback in the growth and obscuration properties of nearby supermassive black holes |
we present the discovery of pso j030947.49+271757.31, the radio brightest (23.7 mjy at 1.4 ghz) active galactic nucleus (agn) at z > 6.0. it was selected by cross-matching the nrao vla sky survey and the panoramic survey telescope and rapid response system ps1 databases and its high-z nature was confirmed by a dedic... | the first blazar observed at z > 6 |
results from a few decades of reverberation mapping (rm) studies have revealed a correlation between the radius of the broad-line emitting region (blr) and the continuum luminosity of active galactic nuclei. this "radius-luminosity" relation enables survey-scale black hole mass estimates across cosmic time, using relat... | the sloan digital sky survey reverberation mapping project: the hβ radius-luminosity relation |
the ultraviolet background (uvb) emitted by quasars and galaxies governs the ionization and thermal state of the intergalactic medium (igm), regulates the formation of high-redshift galaxies, and is thus a key quantity for modeling cosmic reionization. the vast majority of cosmological hydrodynamical simulations implem... | self-consistent modeling of reionization in cosmological hydrodynamical simulations |
we produce simulations of the atomic c ii line emission in large sky fields in order to determine the current and future prospects for mapping this line during the high-redshift epoch of reionization. we calculate the c ii line intensity, redshift evolution, and spatial fluctuations using observational relations betwee... | prospects for detecting c ii emission during the epoch of reionization |
we present a new relationship between central black hole (bh) mass and host galaxy stellar bulge mass extending to the lowest bh masses known in dwarf galaxies (m bh ≲ 105 m ⊙ m ⋆ ∼ 109 m ⊙). we have obtained visible and near-infrared hubble space telescope imaging of seven dwarf galaxies with optically selected broad-... | the black hole-bulge mass relation including dwarf galaxies hosting active galactic nuclei |
we report the discovery and spectroscopic confirmation of 22 new gravitationally lensed quasars found using gaia data release 2. the selection was made using several techniques: multiple gaia detections around objects in quasar candidate catalogues, modelling of unwise coadd pixels using gaia astrometry, and gaia detec... | gravitationally lensed quasars in gaia - iii. 22 new lensed quasars from gaia data release 2 |
x-ray emission from quasars has been detected up to redshift z = 7.5, although only limited to a few objects at z > 6.5. in this work, we present new chandra observations of five z > 6.5 quasars. by combining with archival chandra observations of six additional z > 6.5 quasars, we perform a systematic analysis... | revealing the accretion physics of supermassive black holes at redshift z ∼ 7 with chandra and infrared observations |
in this paper, we present a model-independent approach to calibrate the largest quasar sample. calibrating quasar samples is essentially constraining the parameters of the linear relation between the log of the ultraviolet (uv) and x-ray luminosities. this calibration allows quasars to be used as standardized candles. ... | hubble diagram at higher redshifts: model independent calibration of quasars |
context. sources at the brightest end of the quasi-stellar object (qso) luminosity function, during the peak epoch in the history of star formation and black hole accretion (z ∼ 2-4, often referred to as "cosmic noon") are privileged sites to study the cycle of feeding & feedback processes in massive galaxies.aims:... | the wissh quasars project. ix. cold gas content and environment of luminous qsos at z ∼ 2.4-4.7 |
we study the optical gri photometric variability of a sample of 190 quasars within the sdss stripe 82 region that have long-term photometric coverage during ~1998-2020 with sdss, panstarrs-1, the dark energy survey, and dedicated follow-up monitoring with blanco 4m/decam. with on average ~200 nightly epochs per quasar ... | optical variability of quasars with 20-yr photometric light curves |
we present a description of the australian dark energy survey (ozdes) and summarize the results from its 6 years of operations. using the 2df fibre positioner and aaomega spectrograph on the 3.9-m anglo-australian telescope, ozdes has monitored 771 active galactic nuclei, classified hundreds of supernovae, and obtained... | ozdes multi-object fibre spectroscopy for the dark energy survey: results and second data release |
quasars have been proposed as a new class of standard candles analogous to supernovae, since their large redshift range and high luminosities make them excellent candidates. the reverberation mapping (rm) method enables one to estimate the distance to the source from the time delay measurement of the emission lines wit... | can reverberation-measured quasars be used for cosmology? |
we present results from the first 12 months of operation of radio galaxy zoo, which upon completion will enable visual inspection of over 170 000 radio sources to determine the host galaxy of the radio emission and the radio morphology. radio galaxy zoo uses 1.4 ghz radio images from both the faint images of the radio ... | radio galaxy zoo: host galaxies and radio morphologies derived from visual inspection |
using a single gravitational lens system observed at ≲ 5 mas resolution with very long baseline interferometry, we place a lower bound on the mass of the fuzzy dark matter (fdm) particle, ruling out mχ ≤ 4.4 × 10-21 ev with a 20:1 posterior odds ratio relative to a smooth lens model. we generalize our result to non-sca... | a lensed radio jet at milli-arcsecond resolution - ii. constraints on fuzzy dark matter from an extended gravitational arc |
we present new alma band-7 data for a sample of six luminous quasars at z≃ 4.8, powered by fast-growing supermassive black holes (smbhs) with rather uniform properties: the typical accretion rates and black hole masses are l/{l}{edd}≃ 0.7 and {m}{bh}≃ {10}9 {m}⊙ . our sample consists of three “fir-bright” sources, whic... | alma observations show major mergers among the host galaxies of fast-growing, high-redshift\u200b supermassive\u200b black holes |
cosmography is a powerful tool for investigating the universe kinematic and then for reconstructing the dynamics in a model-independent way. however, recent new measurements of supernovae ia and quasars have populated the hubble diagram up to high redshifts (z ∼ 7.5) and the application of the traditional cosmographic ... | cosmography by orthogonalized logarithmic polynomials |
the desi survey will measure large-scale structure using quasars as direct tracers of dark matter in the redshift range 0.9 < z < 2.1 and using quasar lyα forests at z > 2.1. we present two methods to select candidate quasars for desi based on imaging in three optical (g, r, z) and two infrared (w1, w2) bands.... | preliminary target selection for the desi quasar (qso) sample |
the time delay measured between the images of gravitationally lensed quasars probes a combination of the angular diameter distance to the source-lens system and the mass density profile of the lens. observational campaigns to measure such systems have reported a determination of the hubble parameter h0 that shows signi... | could quasar lensing time delays hint to a core component in halos, instead of h0 tension? |
in this third paper of the series reporting on the reverberation mapping campaign of active galactic nuclei with asymmetric hβ emission-line profiles, we present results for 15 palomar-green quasars using spectra obtained between the end of 2016-2021 may. this campaign combines long time spans with relatively high cade... | monitoring agns with hβ asymmetry. iii. long-term reverberation mapping results of 15 palomar-green quasars |
the concept of the quasar main sequence is very attractive since it stresses correlations between various parameters and implies the underlying simplicity. in the optical plane defined by the width of the hβ line and the ratio of the equivalent width of the fe ii to hβ observed objects form a characteristic pattern. in... | modeling of the quasar main sequence in the optical plane |
in this work, we include black hole (bh) seeding, growth, and feedback into our semi-analytic galaxy formation model, delphi. our model now fully tracks the accretion- and merger-driven hierarchical assembly of the dark matter halo, gas, stellar, and bh masses of high-redshift (z ≳ 5) galaxies. we explore a number of p... | the hierarchical assembly of galaxies and black holes in the first billion years: predictions for the era of gravitational wave astronomy |
the mass and the spin of accreting and jetted black holes, at the center of active galactic nuclei (agns), can be probed by analyzing their electromagnetic spectra. for this purpose, we use the spin-modified fundamental plane of black hole activity, which non-linearly connects the following four variables (in the sourc... | properties of ultralight bosons from heavy quasar spins via superradiance |
we present initial results from the cosmic origins spectrograph (cos) and gemini mapping the circumgalactic medium (cgmcgm ≡ cgm2) survey. the cgm2 survey consists of 1689 galaxies, all with high-quality gemini-gmos spectra, within 1 mpc of 22 z ≲ 1 quasars, all with a signal-to-noise ratio of ∼10 hubble space telescop... | cgm2 i: the extent of the circumgalactic medium traced by neutral hydrogen |
results from regular monitoring of relativistic compact binaries like psr 1913+16 are consistent with the dominant (quadrupole) order emission of gravitational waves (gws). we show that observations associated with the binary black hole (bbh) central engine of blazar oj 287 demand the inclusion of gravitational radiati... | authenticating the presence of a relativistic massive black hole binary in oj 287 using its general relativity centenary flare: improved orbital parameters |
observations of high-redshift quasars provide information on the massive black holes (mbhs) powering them and the galaxies hosting them. current observations of z ≳ 6 hosts, at sub-millimetre wavelengths, trace the properties of cold gas, and these are used to compare with the correlations between mbhs and galaxies cha... | high-redshift quasars and their host galaxies - i. kinematical and dynamical properties and their tracers |
proximity zone fossils (pzfs) are ionization signatures around recently active galactic nuclei (agns) where metal species in the circumgalactic medium remain overionized after the agns have shut off due to their long recombination time scales. we explore cosmological zoom hydrodynamic simulations, using the eagle (evol... | flickering agn can explain the strong circumgalactic o vi observed by cos-halos |
the x-ray and mid-ir emission from active galactic nuclei (agns) are strongly correlated. however, while various published parameterizations of this correlation are consistent with the low-redshift, local seyfert galaxy population, extrapolations of these relations to high luminosity differ by an order of magnitude at ... | the x-ray to mid-infrared relation of agns at high luminosity |
supermassive black holes (bhs) reside in the centre of most local galaxies, but they also power active galactic nuclei and quasars, detected up to z = 7. these quasars put constraints on early bh growth and the mass of bh seeds. the scenario of `direct collapse' is appealing as it leads to the formation of large mass b... | on the number density of `direct collapse' black hole seeds |
we present a computationally efficient and fast semi-numerical technique for simulating the lyman α (ly α) absorption optical depth in presence of neutral hydrogen 'islands' left over from reionization at redshifts 5 ≲ z ≲ 6. the main inputs to the analysis are (i) a semi-numerical photon-conserving model of ionized re... | studying the lyman α optical depth fluctuations at z ∼ 5.5 using fast semi-numerical methods |
so far large and different data sets revealed the accelerated expansion rate of the universe, which is usually explained in terms of dark energy. the nature of dark energy is not yet known, and several models have been introduced: a non-zero cosmological constant, a potential energy of some scalar field, effects relate... | prospects of high redshift constraints on dark energy models with the ep, i - eiso correlation in long gamma ray bursts |
we report the discovery, spectroscopic confirmation, and preliminary characterization of 24 gravitationally lensed quasars identified using gaia observations. candidates were selected in the pan-starrs footprint with quasar-like wise colours or as photometric quasars from sloan digital sky survey (sdss), requiring eith... | gravitationally lensed quasars in gaia - ii. discovery of 24 lensed quasars |
in an effort to search for ly α emission from circum- and intergalactic gas on scales of hundreds of kpc around z ∼ 3 quasars, and thus characterize the physical properties of the gas in emission, we have initiated an extensive fast survey with the multi-unit spectroscopic explorer (muse): quasar snapshot observations ... | inspiraling halo accretion mapped in ly α emission around a z ∼ 3 quasar |
stars can either be formed in or captured by the accretion disks in active galactic nuclei (agns). these agn stars are irradiated and subject to extreme levels of accretion, which can turn even low-mass stars into very massive ones (m > 100m⊙) whose evolution may result in the formation of massive compact objects (m... | stellar evolution in the disks of active galactic nuclei produces rapidly rotating massive stars |
galaxy mergers occur frequently in the early universe1 and bring multiple supermassive black holes (smbhs) into the nucleus, where they may eventually coalesce. identifying post-merger-scale (that is, less than around a few kpc) dual smbhs is a critical pathway to understanding their dynamical evolution and successive ... | a hidden population of high-redshift double quasars unveiled by astrometry |
we present the first results of a project called sagan, which is dedicated solely to the studies of relatively rare megaparsec-scale radio galaxies in the universe, called giant radio galaxies (grgs). we have identified 162 new grgs primarily from the nrao vla sky survey with sizes ranging from ∼0.71 mpc to ∼2.82 mpc i... | search and analysis of giant radio galaxies with associated nuclei (sagan). i. new sample and multi-wavelength studies |
the far-infrared fine-structure line [c ii] at 1900.5 ghz is known to be one of the brightest cooling lines in local galaxies, and therefore it has been suggested to be an efficient tracer for star formation in very high redshift galaxies. however, recent results for galaxies at z > 6 have yielded numerous non-detec... | [c ii] emission in z ∼ 6 strongly lensed, star-forming galaxies |
ly α emission lines are typically found to be redshifted with respect to the systemic redshifts of galaxies, likely due to resonant scattering of ly α photons. here, we measure the average velocity offset for a sample of 96 z ≈ 3.3 ly α emitters (laes) with a median ly α flux (luminosity) of ≈10<>sup>-17 erg c... | musequbes: calibrating the redshifts of ly α emitters using stacked circumgalactic medium absorption profiles |
starting from a summary of detection statistics of our recent x-shooter campaign, we review the major surveys, both space and ground based, for emission counterparts of high-redshift damped ly α absorbers (dlas) carried out since the first detection 25 yr ago. we show that the detection rates of all surveys are precise... | consensus report on 25 yr of searches for damped ly α galaxies in emission: confirming their metallicity-luminosity relation at z ≳ 2 |
the observed scatter in intergalactic lyα opacity at z ≲ 6 requires large-scale fluctuations in the neutral fraction of the intergalactic medium (igm) after the expected end of reionization. post-reionization models that explain this scatter invoke fluctuations in either the ionizing ultraviolet background (uvb) or igm... | evidence for large-scale fluctuations in the metagalactic ionizing background near redshift six |
we present 0.″035 resolution (~200 pc) imaging of the 158 μm [c ii] line and the underlying dust continuum of the z = 6.9 quasar j234833.34-305410.0. the 18 hour atacama large millimeter/submillimeter array observations reveal extremely compact emission (diameter ~1 kpc) that is consistent with a simple, almost face-on... | alma 200 pc imaging of a z 7 quasar reveals a compact, disk-like host galaxy |
using six years of spectroscopic monitoring of the luminous quasar he 0435-4312 (z = 1.2231) with the southern african large telescope, in combination with photometric data (catalina, ogle, salticam, and bmt), we determined a rest-frame time delay of ${296}_{-14}^{+13}$ days between the mg ii broad-line emission and th... | time delay of mg ii emission response for the luminous quasar he 0435-4312: toward application of the high-accretor radius-luminosity relation in cosmology |
we present trinity, a flexible empirical model that self-consistently infers the statistical connection between dark matter haloes, galaxies, and supermassive black holes (smbhs). trinity is constrained by galaxy observables from 0 < z < 10 [galaxies' stellar mass functions, specific and cosmic star formation rat... | trinity i: self-consistently modelling the dark matter halo-galaxy-supermassive black hole connection from z = 0-10 |
we present cosmological results inferred from the effective-field theory (eft) analysis of the full-shape of eboss quasars (qso) power spectrum. we validate our analysis pipeline against simulations, and find overall good agreement between the analyses in fourier and configuration space. keeping the baryon abundance an... | cosmological inference from the eftoflss: the eboss qso full-shape analysis |
we report new northern extended millimeter array observations of the [c ii]158 μm, [n ii]205 μm, and [o i]146 μm atomic fine structure lines (fsls) and dust continuum emission of j1148+5251, a z = 6.42 quasar, which probe the physical properties of its interstellar medium (ism). the radially averaged [c ii]158 μm and d... | physical constraints on the extended interstellar medium of the z = 6.42 quasar j1148+5251: [c ii]158 μm, [n ii]205 μm, and [o i]146 μm observations |
the growth of the most massive black holes in the early universe, consistent with the detection of highly luminous quasars at z > 6 implies sustained, critical accretion of material to grow and power them. given a black hole (bh) seed scenario, it is still uncertain which conditions in the early universe allow the f... | the origin of the most massive black holes at high-z: bluetides and the next quasar frontier |
we decompose the lyman-α (lyα) forest of an extensive sample of 75 high signal-to-noise ratio and high-resolution quasar spectra into a collection of voigt profiles. absorbers located near caustics in the peculiar velocity field have the smallest doppler parameters, resulting in a low-b cutoff in the b-{n}{{h}{{i}}} di... | a new measurement of the temperature-density relation of the igm from voigt profile fitting |
the interstellar medium is crucial to understanding the physics of active galaxies and the coevolution between supermassive black holes and their host galaxies. however, direct gas measurements are limited by sensitivity and other uncertainties. dust provides an efficient indirect probe of the total gas. we apply this ... | on the gas content and efficiency of agn feedback in low-redshift quasars |
we investigate the contribution of reprocessed continuum emission (1000-10 000 å) originating in broad-line region (blr) gas, the diffuse continuum (dc), to the wavelength-dependent continuum delays measured in agn disc reverberation mapping experiments. assuming a spherical blr geometry, we adopt a local optimally emi... | quantifying the impact of variable blr diffuse continuum contributions on measured continuum interband delays |
numerical simulations of cosmological structure formation show that the universe’s most massive clusters, and the galaxies living in those clusters, assemble rapidly at early times (2.5\lt z\lt 4). while more than 20 proto-clusters have been observed at z≳ 2 based on associations of 5-40 galaxies around rare sources, t... | a massive, distant proto-cluster at z = 2.47 caught in a phase of rapid formation? |
approximately 200 supermassive black holes (smbhs) have been discovered within the first ∼gigayear after the big bang. one pathway for the formation of smbhs is through the collapse of supermassive stars (smss). a possible obstacle to this scenario is that the collapsing gas fragments and forms a cluster of main-sequen... | making a supermassive star by stellar bombardment |
we explore the circumgalactic metal content traced by commonly observed low ion absorbers, including c ii, si ii, si iii, si iv, and mg ii. we use a set of cosmological hydrodynamical zoom simulations run with the eagle model and including a non-equilibrium ionization and cooling module that follows 136 ions. the simul... | the multiphase circumgalactic medium traced by low metal ions in eagle zoom simulations |
we present the first self-consistent prediction for the distribution of formation time-scales for close supermassive black hole (smbh) pairs following galaxy mergers. using romulus25, the first large-scale cosmological simulation to accurately track the orbital evolution of smbhs within their host galaxies down to sub-... | dancing to changa: a self-consistent prediction for close smbh pair formation time-scales following galaxy mergers |
we study the molecular gas properties of high-z galaxies observed in the alma spectroscopic survey (aspecs) that targets an ∼1 arcmin2 region in the hubble ultra deep field (udf), a blind survey of co emission (tracing molecular gas) in the 3 and 1 mm bands. of a total of 1302 galaxies in the field, 56 have spectroscop... | the alma spectroscopic survey in the hubble ultra deep field: molecular gas reservoirs in high-redshift galaxies |
we imaged, with alma and argos/luci, the molecular gas and dust and stellar continuum in xid2028, which is an obscured quasi-stellar object (qso) at z = 1.593, where the presence of a massive outflow in the ionised gas component traced by the [oiii]5007 emission has been resolved up to 10 kpc. this target represents a ... | molecular outflow and feedback in the obscured quasar xid2028 revealed by alma |
ngc 1266 is a nearby lenticular galaxy that harbors a massive outflow of molecular gas powered by the mechanical energy of an active galactic nucleus (agn). it has been speculated that such outflows hinder star formation (sf) in their host galaxies, providing a form of feedback to the process of galaxy formation. previ... | suppression of star formation in ngc 1266 |
our understanding of the unification of jetted agn has evolved greatly as jet samples have increased in size. here, based on the largest-ever sample of over 2000 well-sampled jet spectral energy distributions, we examine the synchrotron peak frequency - peak luminosity plane, and find little evidence for the anticorrel... | the relativistic jet dichotomy and the end of the blazar sequence |
the properties of quasar-host galaxies might be determined by the growth and feedback of their supermassive black holes (smbhs, 108-10 m⊙). we investigate such connection with a suite of cosmological simulations of massive (halo mass ≈1012 m⊙) galaxies at z ≃ 6 that include a detailed subgrid multiphase gas and accreti... | host galaxies of high-redshift quasars: smbh growth and feedback |
we present a multiline survey of the interstellar medium (ism) in two z > 6 quasar host galaxies, pj231−20 (z = 6.59) and pj308−21 (z = 6.23), and their two companion galaxies. observations were carried out using the atacama large (sub-)millimeter array (alma). we targeted 11 transitions including atomic fine-struct... | alma multiline survey of the ism in two quasar host-companion galaxy pairs at z > 6 |
millions of quasar spectra will be collected by the dark energy spectroscopic instrument (desi), leading to a fourfold increase in the number of known quasars. high-accuracy quasar classification is essential to tighten constraints on cosmological parameters measured at the highest redshifts desi observes (z > 2.0).... | performance of the quasar spectral templates for the dark energy spectroscopic instrument |
using a sample of ≃144 000 quasars from the sloan digital sky survey data release 14, we investigate the outflow properties, evident in both absorption and emission, of high-ionization broad absorption line (bal) and non-bal quasars with redshifts 1.6 ≲ z ≤ 3.5 and luminosities 45.3 erg s-1 < log10(lbol) < 48.2 e... | bal and non-bal quasars: continuum, emission, and absorption properties establish a common parent sample |
we use cosmological hydrodynamical simulations to investigate the role of feedback from accreting black holes in the evolution of the size, compactness, stellar core density, and specific star formation of massive galaxies with stellar masses of {m}* > {10}10.9 {m}⊙ . we perform two sets of cosmological zoom-in simu... | the role of black hole feedback on size and structural evolution in massive galaxies |
lyα forest data probing the post-reionization universe show surprisingly large opacity fluctuations over rather large (≥50 h-1 comoving mpc) spatial scales. we model these fluctuations using a hybrid approach utilizing the large-volume millennium simulation to predict the spatial distribution of qsos combined with smal... | large-scale opacity fluctuations in the lyα forest: evidence for qsos dominating the ionizing uv background at z ∼ 5.5-6? |
strong gravitational lensing provides a powerful test of cold dark matter (cdm) as it enables the detection and mass measurement of low-mass haloes even if they do not contain baryons. compact lensed sources such as active galactic nuclei (agns) are particularly sensitive to perturbing subhaloes, but their use as a tes... | probing dark matter substructure in the gravitational lens he 0435-1223 with the wfc3 grism |
we study the distribution and kinematics of the cool circumgalactic medium (cgm) of emission line galaxies (elgs) traced by metal absorption lines. using about 200,000 elgs from sdss-iv eboss and half a million background quasars from sdss, we measure the median absorption strength of mg ii and fe ii lines in quasar sp... | the circumgalactic medium of eboss emission line galaxies: signatures of galactic outflows in gas distribution and kinematics |
the supermassive black holes (smbhs) observed at the centers of all massive galaxies are believed to have grown via luminous accretion during quasar phases in the distant past. the fraction of inflowing rest mass energy emitted as light, the radiative efficiency, has been inferred to be 10%, in agreement with expectati... | evidence for low radiative efficiency or highly obscured growth of z > 7 quasars |
the growth of the first supermassive black holes (smbhs) at z > 6 is still a major challenge for theoretical models. if it starts from black hole (bh) remnants of population iii stars (light seeds with mass ∼100 m⊙), it requires super-eddington accretion. an alternative route is to start from heavy seeds formed by t... | from the first stars to the first black holes |
we assume that dust near active galactic nuclei (agns) is distributed in a torus-like geometry, which can be described as a clumpy medium or a homogeneous disk, or as a combination of the two (i.e. a two-phase medium). the dust particles considered are fluffy and have higher submillimeter emissivities than grains in th... | self-consistent two-phase agn torus models⋆. sed library for observers |
1es 1927+654 is a nearby active galactic nucleus (agn) that underwent a changing-look event in early 2018, developing prominent broad balmer lines that were absent in previous observations. we have followed up this object in the x-rays with an ongoing campaign that started in 2018 may and that includes 265 nicer (for a... | the 450 day x-ray monitoring of the changing-look agn 1es 1927+654 |
we perform a joint bao and rsd analysis using the eboss dr16 lrg and elg samples in the redshift range of z ∈ [0.6, 1.1], and detect an rsd signal from the cross-power spectrum at a ~4σ confidence level, i.e., fσ8 = 0.317 ± 0.080 at zeff = 0.77. based on the chained power spectrum, which is a new development in this wo... | the completed sdss-iv extended baryon oscillation spectroscopic survey: a multitracer analysis in fourier space for measuring the cosmic structure growth and expansion rate |
in this paper, we quantify the ability of multiple measurements of high-redshift quasars to constrain several theories of modified gravity, including the dvali-gabadadze-porrati braneworld scenario, generalized chaplygin gas, f(t) modified gravity, and modified polytropic cardassian model. recently released sample of 1... | probing modified gravity theories with multiple measurements of high-redshift quasars |
the ~100 tidal disruption events (tdes) observed so far exhibit a wide range of emission properties both at peak and over their lifetimes. some tdes radiate predominantly at x-ray energies, while others radiate chiefly at uv and optical wavelengths. while the peak luminosities across tdes show distinct properties, the ... | dynamical unification of tidal disruption events |
quasars are associated with and powered by the accretion of material onto massive black holes; the detection of highly luminous quasars with redshifts greater than z = 6 suggests that black holes of up to ten billion solar masses already existed 13 billion years ago. two possible present-day ‘dormant’ descendants of th... | a 17-billion-solar-mass black hole in a group galaxy with a diffuse core |
we characterize the optical variability of quasars in the palomar transient factory and intermediate palomar transient factory (ptf/iptf) surveys. we re-calibrate the r-band light curves for ∼28,000 luminous, broad-line active galactic nuclei from the sdss, producing a total of ∼2.4 million photometric data points. we ... | optical variability of agns in the ptf/iptf survey |
the hyper suprime-cam subaru strategic program (hsc-ssp) is an excellent survey for the search for strong lenses, thanks to its area, image quality, and depth. we use three different methods to look for lenses among 43000 luminous red galaxies from the baryon oscillation spectroscopic survey (boss) sample with photomet... | survey of gravitationally-lensed objects in hsc imaging (sugohi). i. automatic search for galaxy-scale strong lenses |
interpreting abundances of damped ly-α absorbers (dlas) from absorption-line spectroscopy has typically been a challenge because of the presence of dust. nevertheless, because dlas trace distant gas-rich galaxies regardless of their luminosity, they provide an attractive way of measuring the evolution of the metallicit... | the cosmic evolution of dust-corrected metallicity in the neutral gas |
we test the consistency of active galactic nuclei (agn) optical flux variability with the damped random walk (drw) model. our sample consists of 20 multiquarter kepler agn light curves including both type 1 and 2 seyferts, radio-loud and -quiet agn, quasars, and blazars. kepler observations of agn light curves offer a ... | are the variability properties of the kepler agn light curves consistent with a damped random walk? |
we present alma observations of two moderate-luminosity quasars at redshift 6. these quasars, from the canada-france high-z quasar survey (cfhqs), have black hole masses of ∼ {{10}8} {{m}⊙ }. both quasars are detected in the [c ii] line and dust continuum. combining these data with our previous study of two similar cfh... | star formation rate and dynamical mass of 108 solar mass black hole host galaxies at redshift 6 |
massive galaxies formed most actively at redshifts z = 1-3 during the period known as "cosmic noon." here we present an emission-line study of the extremely red quasar sdssj165202.64+172852.3's host galaxy at z = 2.94, based on observations with the near infrared spectrograph integral field unit on board jwst. we use s... | first results from the jwst early release science program q3d: ionization cone, clumpy star formation, and shocks in a z = 3 extremely red quasar host |
in this paper, we present photometric redshift (photo-z) estimates for the dark energy spectroscopic instrument (desi) legacy imaging surveys, currently the most sensitive optical survey covering the majority of the extragalactic sky. our photo-z methodology is based on a machine-learning approach, using sparse gaussia... | all-purpose, all-sky photometric redshifts for the legacy imaging surveys data release 8 |
we investigate the molecular gas content of z ∼ 6 quasar host galaxies using the institut de radioastronomie millimétrique northern extended millimeter array. we targeted the 3 mm dust continuum, and the line emission from co(6-5), co(7-6), and [c i]2−1 in ten infrared-luminous quasars that have been previously studied... | molecular gas in z ∼ 6 quasar host galaxies |
super-eddington accretion is one scenario that may explain the rapid assembly of ∼109 m⊙ supermassive black holes (bhs) within the first billion year of the universe. this critical regime is associated with radiatively inefficient accretion and accompanied by powerful outflows in the form of winds and jets. by means of... | how the super-eddington regime regulates black hole growth in high-redshift galaxies |
quasar feedback may regulate the growth of supermassive black holes, quench coeval star formation, and impact galaxy morphology and the circumgalactic medium. however, direct evidence for quasar feedback in action at the epoch of peak black hole accretion at z ≈ 2 remains elusive. a good case in point is the z = 1.6 qu... | first results from the jwst early release science program q3d: the warm ionized gas outflow in z 1.6 quasar xid 2028 and its impact on the host galaxy |
we review the current status of knowledge concerning the early phases of star formation during cosmic dawn. this includes the first generations of stars forming in the lowest mass dark matter halos in which cooling and condensation of gas with primordial composition is possible at very high redshift (z >20 ), namely... | formation of the first stars and black holes |
we study the interstellar medium in a sample of 27 high-redshift quasar host galaxies at z ≳ 6, using the [c ii] 158 μm emission line and the underlying dust continuum observed at ∼1 kpc resolution with atacama large millimeter array. by performing uv-plane spectral stacking of both the high and low spatial resolution ... | no evidence for [c ii] halos or high-velocity outflows in z ≳ 6 quasar host galaxies |
observations reveal that quasar host haloes at z ∼ 2 have large covering fractions of cool dense gas (≳60 per cent for lyman limit systems within a projected virial radius). most simulations have so far failed to explain these large observed covering fractions. we analyse a new set of 15 simulated massive haloes with e... | a stellar feedback origin for neutral hydrogen in high-redshift quasar-mass haloes |
we explore the cosmological implications of anisotropic clustering measurements of the quasar sample from data release 14 (dr14) of the sloan digital sky survey iv extended baryon oscillation spectroscopic survey (eboss) in configuration space. the {∼ } 147 000 quasar sample observed by eboss offers a direct tracer of ... | the clustering of the sdss-iv extended baryon oscillation spectroscopic survey dr14 quasar sample: anisotropic clustering analysis in configuration space |
we investigate the evolution of supermassive black holes in the `evolution and assembly of galaxies and their environments' (eagle) cosmological hydrodynamic simulations. the largest of the eagle volumes covers a (100 cmpc)3 and includes state-of-the-art physical models for star formation and black hole growth that dep... | supermassive black holes in the eagle universe. revealing the observables of their growth |
there is a large degree of variety in the optical variability of quasars and it is unclear whether this is all attributable to a single (set of) physical mechanism(s). we present the results of a systematic search for major flares in active galactic nucleus (agn) in the catalina real-time transient survey as part of a ... | understanding extreme quasar optical variability with crts - i. major agn flares |
determining when and how the first galaxies reionised the intergalactic medium promises to shed light on both the nature of the first objects and the cosmic history of baryons. towards this goal, quasar absorption lines play a unique role by probing the properties of diffuse gas on galactic and intergalactic scales. in... | reionisation and high-redshift galaxies: the view from quasar absorption lines |
following a quasi model-independent approach we measure the transversal bao mode at high redshift using the two-point angular correlation function (2pacf). the analyses done here are only possible now with the quasar catalogue from the twelfth data release (dr12q) from the sloan digital sky survey, because it is spatia... | angular baryon acoustic oscillation measure at z=2.225 from the sdss quasar survey |
the time delays of gravitationally lensed quasars are generally believed to be unique numbers whose measurement is limited only by the quality of the light curves and the models for the contaminating contribution of gravitational microlensing to the light curves. this belief is incorrect - gravitational microlensing al... | microlensing makes lensed quasar time delays significantly time variable |
we constrain and update the bounds on the lifetime of a decaying dark matter model with a warm massive daughter particle using the most recent low-redshift probes. we use supernovae type-ia, baryon acoustic oscillations and the time delay measurements of gravitationally lensed quasars. these data sets are complemented ... | late-time decaying dark matter: constraints and implications for the h0-tension |
accretion discs around active galactic nuclei (agns) are potentially unstable to star formation at large radii. we note that when the compact objects formed from some of these stars spiral into the central supermassive black hole (smbh), there is no radiative feedback and therefore the accretion rate is not limited by ... | star formation in accretion discs and smbh growth |
using our cosmological radiative transfer code, we study the implications of the updated quasi-stellar object (qso) emissivity and star formation history for the escape fraction (fesc) of hydrogen ionizing photons from galaxies. we estimate the fesc that is required to reionize the universe and to maintain the ionizati... | the redshift evolution of escape fraction of hydrogen ionizing photons from galaxies |
stellar-mass black hole binaries (bhbs) near supermassive black holes (smbh) in galactic nuclei undergo eccentricity oscillations due to gravitational perturbations from the smbh. previous works have shown that this channel can contribute to the overall bhb merger rate detected by the laser interferometer gravitational... | detecting supermassive black hole-induced binary eccentricity oscillations with lisa |
discrepancies between reported structure function (sf) slopes and their overall flatness as compared to the expectations from the damped random walk (drw) model, which generally well describes the variability of active galactic nuclei (agns), have triggered us to study this problem in detail. we review common agn varia... | revisiting stochastic variability of agns with structure functions |
using a bayesian framework, we quantify what current observations imply about the history of the epoch of reionization (eor). we use a popular, three-parameter eor model, flexible enough to accommodate a wide range of physically plausible reionization histories. we study the impact of various eor observations: (i) the ... | the global history of reionization |
recent observations of extreme variability in active galactic nuclei have pushed standard viscous accretion disk models over the edge. i suggest either that some kind of non-local physics dominates accretion disks, or that the optical output we see comes entirely from reprocessing a central source. | quasar viscosity crisis |
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