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m 31 has experienced a recent tumultuous merger history, as evidenced from the many substructures that are still present in its inner halo, particularly the g1-clump, ne-, and w-shelves and the giant stream (gs). we present planetary nebulae (pne) line-of-sight velocity (losv) measurements covering the entire spatial e... | the survey of planetary nebulae in andromeda (m 31) vi. kinematics of m 31 inner-halo substructures and comparison with major-merger simulation predictions |
to understand how massive galaxies at high z coevolve with enormous reservoirs of halo gas, it is essential to study the coldest phase of the circumgalactic medium (cgm), which directly relates to stellar growth. the supercold-cgm survey is the first statistical survey of cold molecular gas on cgm scales. we present at... | the supercold-cgm survey. i. probing the extended co(4-3) emission of the circumgalactic medium in a sample of 10 enormous lyα nebulae at z 2 |
the remarkably tight relationship between galaxy optical color and stellar mass-to-light ratio (m */l) is widely used for efficient stellar mass estimates. however, it remains unclear whether this low scatter comes from a natural order in the galaxy population, or whether it is driven by simple relationships in the mod... | flexible models for galaxy star formation histories both shift and scramble the optical color-mass-to-light ratio (m/l) relationship |
context. understanding the wavelength dependence of dust attenuation is vital for inferring the properties of galaxies from their spectral energy distribution (sed) fitting. the dust attenuation curves in star-forming galaxies depend on the complex interplay between the intrinsic physical dust properties and dust-to-st... | dust attenuation law in jwst galaxies at z ∼ 7-8 |
modern wide-field, optical time-domain surveys must solve a basic optimization problem: maximize the number of transient discoveries or minimize the follow-up needed for the new discoveries. here, we describe the color me intrigued experiment, the first from the intermediate palomar transient factory (iptf) to search f... | color me intrigued: the discovery of iptf 16fnm, an sn 2002cx-like object |
one of the major puzzles in the study of stellar evolution is the formation process of bipolar and multipolar planetary nebulae. there is growing consensus that collimated jets create cavities with dense walls in the slowly expanding (10-20 km s-1) envelope ejected in previous evolutionary phases, leading to the observ... | shaping the envelope of the asymptotic giant branch star w43a with a collimated fast jet |
nova cen 2013 (v1369 cen) is the fourth bright nova observed panchromatically through high-resolution uv+optical multiepoch spectroscopy. it is also the nova with the richest set of spectra (in terms of both data quality and number of epochs) thanks to its exceptional brightness. here, we use the late nebular spectra t... | v1369 cen high-resolution panchromatic late nebular spectra in the context of a unified picture for nova ejecta |
the nearby type ia supernovae (sne ia) 2011fe and 2011by had nearly identical photospheric phase optical spectra, light-curve widths, and photometric colours, but at peak brightness sn 2011by reached a fainter absolute magnitude in all optical bands and exhibited lower flux in the near-ultraviolet (nuv). based on those... | twins for life? a comparative analysis of the type ia supernovae 2011fe and 2011by |
the compton spectrometer and imager (cosi), formerly known as the nuclear compton telescope (nct), is a balloon-borne soft gamma-ray telescope (0.2-5 mev) designed to study astrophysical sources of nuclear-line emission and gamma-ray polarization. the heart of cosi is a compact array of cross-strip germanium detectors ... | the upcoming balloon campaign of the compton spectrometer and imager (cosi) |
we examine the spectroscopic binary population for two massive nearby regions of clustered star formation, the orion nebula cluster (onc) and ngc 2264, supplementing the data presented by tobin et al. with more recent observations and more extensive analysis. the inferred multiplicity fraction up to 10 au based on thes... | spectroscopic binaries in the orion nebula cluster and ngc 2264 |
particle acceleration induced by magnetic reconnection is thought to be a promising candidate for producing the nonthermal emissions associated with explosive phenomena such as solar flares, pulsar wind nebulae, and jets from active galactic nuclei. laboratory experiments can play an important role in the study of the ... | particle acceleration in laser-driven magnetic reconnection |
we present a new approach to study planetary nebulae using integral field spectroscopy. vlt@vimos datacube of the planetary nebula abell 14 is analysed in three different ways by extracting: (i) the integrated spectrum, (ii) one-dimensional simulated long-slit spectra for different position angles, and (iii) spaxel-by-... | exploring the differences of integrated and spatially resolved analysis using integral field unit data: the case of abell 14 |
aims: we aim to determine individual distances to a small number of rather round, quite regularly shaped planetary nebulae by combining their angular expansion in the plane of the sky with a spectroscopically measured expansion along the line of sight.methods: we combined up to three epochs of hubble space telescope im... | expansion patterns and parallaxes for planetary nebulae |
we interpret γ-ray flares from the crab nebula as the signature of turbulence in the pulsar’s electromagnetic outflow. turbulence is triggered upstream by dynamical instability of the wind’s oscillating magnetic field and accelerates non-thermal particles. on impacting the wind-termination shock, these particles emit a... | crab flares due to turbulent dissipation of the pulsar striped wind |
we study the nature of feedback mechanisms in the 11 clash brightest cluster galaxies (bcgs) that exhibit extended ultraviolet and nebular line emission features. we estimate star formation rates (sfrs), dust masses, and starburst durations using a bayesian photometry-fitting technique that accounts for both stellar an... | the relationship between brightest cluster galaxy star formation and the intracluster medium in clash |
fast radio bursts (frbs) are mysterious transient sources. if extragalactic, as suggested by their relative large dispersion measures, their brightness temperatures must be extremely high. some frb models (e.g., young pulsar model, magnetar giant flare model, or supra-massive neutron star collapse model) suggest that t... | synchrotron heating by a fast radio burst in a self-absorbed synchrotron nebula and its observational signature |
combined with measurements made by very-long-baseline interferometry, the observations of fast tev gamma-ray flares probe the structure and emission mechanism of blazar jets. however, only a handful of such flares have been detected to date, and only within the last few years have these flares been observed from lower-... | multiwavelength observations of the blazar bl lacertae: a new fast tev gamma-ray flare |
r-matrix calculations combined with the adiabatic nuclei approximation are used to compute electron-impact rotational excitation rates for three closed-shell diatomic cations, heh+, ch+, arh+. comparisons with previous studies show that an improved treatment of threshold effects leads to significant changes in the low ... | electron-impact excitation of diatomic hydride cations - i. heh+, ch+, arh+ |
the radio source 3c 264, hosted by the giant elliptical galaxy ngc 3862, was observed with the very energetic radiation imaging telescope array system (veritas) between 2017 february and 2019 may. these deep observations resulted in the discovery of very high energy (vhe; e > 100 gev) γ-ray emission from this active... | veritas discovery of vhe emission from the radio galaxy 3c 264: a multiwavelength study |
in view of the many recent observations conducted by alma and sphere, it is becoming clear that protoplanetary disks form planets in narrow annular gaps at various distances from the central protostars before these protostars are actually fully formed and the gaseous disks have concluded their accretion/dispersal proce... | on the formation of our solar system and many other protoplanetary systems observed by alma and sphere |
we report comprehensive multi-wavelength observations of a peculiar type ia-like supernova (“sn ia-pec”) asassn-15pz. asassn-15pz is a spectroscopic “twin” of sn 2009dc, a so-called “super-chandrasekhar-mass” sn, throughout its evolution, but it has a peak luminosity {m}b,{peak}=-19.69+/- 0.12 {mag} that is ≈ 0.6 {mag}... | asassn-15pz: revealing significant photometric diversity among 2009dc-like, peculiar sne ia |
observations by the fermi large area telescope of γ-ray millisecond pulsar (msp) light curves imply copious pair production in their magnetospheres, and not exclusively in those of younger pulsars. such pair cascades may be a primary source of galactic electrons and positrons, contributing to the observed enhancement i... | cosmic-ray positrons from millisecond pulsars |
the chemical content of the planetary nebula ngc 3918 is investigated through deep, high-resolution (r ∼ 40 000) uves (ultraviolet-visual echelle spectrograph) at vlt (very large telescope) spectrophotometric data. we identify and measure more than 750 emission lines, making ours one of the deepest spectra ever taken f... | s-process enrichment in the planetary nebula ngc 3918. results from deep echelle spectrophotometry |
igr j11014-6103 (also known as the lighthouse nebula) is composed of a bow-shock pulsar wind nebula (pwn) and large-scale x-ray jet-like features, all powered by psr j1101-6101. previous observations suggest that the jet features stem from a ballistic jet of relativistic particles. in order to confirm the nature of the... | closer view of the igr j11014-6103 outflows |
i present the automated line fitting algorithm, alfa, a new code which can fit emission line spectra of arbitrary wavelength coverage and resolution, fully automatically. in contrast to traditional emission line fitting methods which require the identification of spectral features suspected to be emission lines, alfa i... | alfa: an automated line fitting algorithm |
we study the optical evolution of the 2015 outburst in v404 cyg, with emphasis on the peculiar nebular phase and subsequent decay to quiescence. from the decay time-scale of the balmer emission associated with the nebula, we measure an outflow mass mwind ≃ 4 × 10-6 m⊙. remarkably, this is ∼100 times larger than the acc... | accretion and outflow in v404 cyg |
the distribution of galaxies on a colour-magnitude diagram reveals a bimodality, featuring a passively evolving red sequence and a star-forming blue cloud. the region between these two, the green valley (gv), represents a fundamental transition where quenching processes operate. we exploit an alternative definition of ... | exploring a new definition of the green valley and its implications |
warm ionized and cold neutral outflows with velocities exceeding 100 km s-1 are commonly observed in galaxies and clusters. however, theoretical studies indicate that ram pressure from a hot wind, driven either by the central active galactic nucleus (agn) or a starburst, cannot accelerate existing cold gas to such high... | dynamics and morphology of cold gas in fast, radiatively cooling outflows: constraining agn energetics with horseshoes |
for mev gamma-ray astronomy, we have developed an electron-tracking compton camera (etcc) as a mev gamma-ray telescope capable of rejecting the radiation background and attaining the high sensitivity of near 1 mcrab in space. our etcc comprises a gaseous time-projection chamber (tpc) with a micro pattern gas detector f... | new readout and data-acquisition system in an electron-tracking compton camera for mev gamma-ray astronomy (smile-ii) |
in this chapter we review a new and rapidly growing area of research in high-energy plasma astrophysics—radiative magnetic reconnection, defined here as a regime of reconnection where radiation reaction has an important influence on the reconnection dynamics, energetics, and/or nonthermal particle acceleration. this in... | radiative magnetic reconnection in astrophysics |
we present a study of the x-ray emission from numerical simulations of hot bubbles in planetary nebulae (pne). high-resolution, two-dimensional, radiation-hydrodynamical simulations of the formation and evolution of hot bubbles in pne, with and without thermal conduction, are used to calculate the x-ray emission and st... | formation and x-ray emission from hot bubbles in planetary nebulae - ii. hot bubble x-ray emission |
we perform a comprehensive analysis of the planetary nebula (pn) ngc 6781 to investigate the physical conditions of each of its ionized, atomic, and molecular gas and dust components and the object’s evolution, based on panchromatic observational data ranging from uv to radio. empirical nebular elemental abundances, co... | the herschel planetary nebula survey (herplans): a comprehensive dusty photoionization model of ngc6781 |
e-astrogam is a gamma-ray space mission to be proposed as the m5 medium-size mission of the european space agency. it is dedicated to the observation of the universe with unprecedented sensitivity in the energy range 0.2 { 100 mev, extending up to gev energies, together with a groundbreaking polarization capability. it... | the e-astrogam gamma-ray space mission |
a newly recognized young galactic supernova (sn) remnant, pa 30 (g123.1+4.6), centered on a hot central star with a ~16,000 km s-1 wind velocity, has recently been proposed to be the result of a double-degenerate merger leading to an sn iax event associated with the guest star of 1181 ce. here we present deep optical [... | discovery of an exceptional optical nebulosity in the suspected galactic sn iax remnant pa 30 linked to the historical guest star of 1181 ce |
models of stellar population synthesis (sps) are the fundamental tool that relates the physical properties of a galaxy to its spectral energy distribution (sed). in this paper, we present dsps: a python package for sps. all of the functionality in dsps is implemented natively in the jax library for automatic differenti... | dsps: differentiable stellar population synthesis |
we present an igm h i tomographic map in a survey volume of $16\times 19\times 131\ {h}^{-3}\ \mathrm{comoving}\ {\mathrm{mpc}}^{3}$ (cmpc3) centered at mammoth-1 nebula and three neighboring quasars at z = 2.3. the mammoth-1 nebula is an enormous lyα nebula (elan), hosted by a type-ii quasar dubbed mammoth1-qso, that ... | three-dimensional distribution map of h i gas and galaxies around an enormous lyα nebula and three qsos at z = 2.3 revealed by the h i tomographic mapping technique |
there is a wide consensus that type ia supernovae (sne ia) originate from the thermonuclear explosion of co white dwarfs (wds), with the lack of hydrogen in the observed spectra as a distinctive feature. here, we present supernova (sn) 2016jae, which was classified as an sn ia from a spectrum obtained soon after its di... | nebular hα emission in type ia supernova 2016jae |
the mass-to-light ratio (m/l) is a key parameter in decomposing galactic rotation curves into contributions from the baryonic components and the dark halo of a galaxy. one direct observational method to determine the disc m/l is by calculating the surface mass density of the disc from the stellar vertical velocity disp... | resolving the disc-halo degeneracy - ii: ngc 6946 |
we discuss the detection of 14 rovibrational lines of ch+, obtained toward the planetary nebula ngc 7027 with the ishell spectrograph on nasa's infrared telescope facility (irtf) on maunakea. our observations in the 3.49-4.13 μm spectral region, obtained with a 0"375 slit width that provided a spectral resolving power ... | observations and analysis of ch+ vibrational emissions from the young, carbon-rich planetary nebula ngc 7027: a textbook example of chemical pumping |
context. the role of feedback in the self-regulation of star formation is a fundamental question in astrophysics. the orion nebula is the nearest site of ongoing and recent massive star formation. it is a unique laboratory for the study of stellar feedback. recent sofia [c ii] 158 μm observations have revealed an expan... | breaking orion's veil with fossil outflows |
low-metallicity, compact starburst galaxies referred to as green peas (gps) provide a unique window to study galactic evolution across cosmic epochs. in this work, we present new deep optical spectra for three gps from osiris at the 10-m gran telescopio canarias, which are studied using a state-of-the-art methodology. ... | new insights on the nebular emission, ionizing radiation, and low metallicity of green peas from advanced modelling |
we present extensive optical/ultraviolet observations and modelling analysis for the nearby sn 1987a-like peculiar type ii supernova (sn) 2018hna. both photometry and spectroscopy covered phases extending to >500 d after the explosion, making it one of the best-observed sn ii of this subtype. sn 2018hna is obviously... | sn 2018hna: adding a piece to the puzzles of the explosion of blue supergiants |
context. the carina nebula is one of the major massive star-forming regions in the galaxy. its relatively nearby distance (2.35 kpc) makes it an ideal laboratory for the study of massive star formation, structure, and evolution, both for individual stars and stellar systems. thanks to the high-quality spectra provided ... | gaia-eso survey: massive stars in the carina nebula. i. a new census of ob stars |
the large-scale diffuse γ − ray flux observed by fermi large area telescope (fermi-lat) in the 1-100 gev energy range, parameterized as ∝ e−γ, has a spectral index γ that depends on the distance from the galactic center. this feature, if attributed to the diffuse emission produced by cosmic rays interactions with the i... | the contribution of galactic tev pulsar wind nebulae to fermi large area telescope diffuse emission |
context. when stripped from their hydrogen-rich envelopes, stars with initial masses between ∼7 and 11 m⊙ may develop massive degenerate cores and collapse. depending on the final structure and composition, the outcome can range from a thermonuclear explosion, to the formation of a neutron star in an electron-capture s... | thermonuclear and electron-capture supernovae from stripped-envelope stars |
a nebular spectrum of the peculiar, low-luminosity type ia supernova 2010lp is modelled in order to estimate the composition of the inner ejecta and to illuminate the nature of this event. despite having a normally declining light curve, sn 2010lp was similar spectroscopically to sn 1991bg at early times. however, it s... | a very low central oxygen mass in the peculiar type ia sn 2010lp: further diversity at the low-luminosity end of sne ia |
we provide a new method for deriving heavy element abundances taking advantage of the unique suite of fine-structure lines in the mid- to far-infrared (ir) range. using grids of photo-ionisation models that cover a wide range in o/h and n/o abundances and ionisation parameter, our code hii-chi-mistry-ir (hcm-ir) provid... | measuring chemical abundances with infrared nebular lines: hii-chi-mistry-ir |
in 1181 ad, chinese and japanese observers reported an unmoving bright 'guest star' in the constellation chuanshe, visible for 185 d. in 2013, d. patchick discovered what turned out to be a unique nebula surrounding a unique star, with the structure named 'pa 30', while subsequent workers made connections to mergers of... | the path from the chinese and japanese observations of supernova 1181 ad, to a type iax supernova, to the merger of co and one white dwarfs |
this work presents theoretical calculations of infrared spectra of nitrogen (n)-containing polycyclic aromatic hydrocarbon (pah) molecules with the incorporation of n, nh, and nh2 using density functional theory (dft). the properties of their vibrational modes in 2-15 μm are investigated in relation to the unidentified... | theoretical study of infrared spectra of interstellar pah molecules with n, nh, and nh2 incorporation |
the large high altitude air shower observatory (lhaaso) observed a dozen gamma-ray sources with significant emission above 100 tev that may be strong candidates for pevatrons. neutrino observations are crucial for diagnosing whether the gamma-ray radiative process is hadronic or leptonic. we use the bayesian method to ... | neutrino observations of lhaaso sources: present constraints and future prospects |
as a science verification study of the newly released akari/fis faint source catalog ver. 1, this paper discusses the different levels of dust attenuation toward stellar light and nebular emission lines within local star-forming galaxies at 0.02 < z < 0.10. by constructing an updated version of the akari-sdss-gal... | on the different levels of dust attenuation to nebular and stellar light in star-forming galaxies |
we report on the properties of the low-mass stars that recently formed in the central ∼ 2\buildrel{ \prime}\over{.} 7× 2\buildrel{ \prime}\over{.} 7 of 30 dor, including the r136 cluster. using the photometric catalog of de marchi et al., based on observations with the hubble space telescope, and the most recent extinc... | photometric determination of the mass accretion rates of pre-main-sequence stars. v. recent star formation in the 30 dor nebula |
if confirmed, the neptune-size exomoon candidate in the kepler 1625 system will be the first natural satellite outside our solar system. its characteristics are nothing alike we know for a satellite. kepler 1625b i is expected to be as massive as neptune and to orbit at 40 planetary radii around a ten jupiter mass plan... | exploring formation scenarios for the exomoon candidate kepler 1625b i |
we have observed the symbiotic stellar system r aqr, aiming to describe the gravitational interaction between the white dwarf (wd) and the wind from the mira star, the key phenomenon driving the symbiotic activity and the formation of nebulae in such systems. we present high-resolution alma maps of the 12co and 13co j ... | high-resolution observations of the symbiotic system r aqr. direct imaging of the gravitational effects of the secondary on the stellar wind |
we present the first high spatial resolution radio continuum survey of the southern galactic plane. the cornish project has mapped the region defined by 295° < l < 350°; |b| < 1° at 5.5 ghz, with a resolution of 2.5 arcsec (fwhm). as with the cornish-north survey, this is designed to primarily provide matching... | the coordinated radio and infrared survey for high-mass star formation - v. the cornish-south survey and catalogue |
we study six luminous lyα emitters (laes) with very blue rest-frame uv continua at 5.7 ≤ z ≤ 6.6. these laes have previous hubble space telescope (hst) and spitzer irac observations. combining our newly acquired hst images, we find that their uv-continuum slopes β are in a range of -3.4 ≤ β ≤ -2.6. unlike previous, ten... | luminous lyα emitters with very blue uv-continuum slopes at redshift 5.7 ≤ z ≤ 6.6 |
we have used the 150 mhz radio continuum survey (tgss adr) from the giant metrewave radio telescope (gmrt) to search for phase-averaged emission toward all well-localized radio pulsars north of -53° decl. we detect emission toward 200 pulsars with high confidence (≥slant 5σ ) and another 88 pulsars at fainter levels. w... | known pulsars identified in the gmrt 150 mhz all-sky survey |
at the age of about 1 yr, the spectra of most type ia supernovae (sne ia) are dominated by strong forbidden nebular emission lines of fe ii and fe iii. later observations (at about 2 yr) of the nearby sn 2011fe showed an unexpected shift of ionization to fe i and fe ii. spectra of the very nearby sn ia 2014j at an inte... | the intermediate nebular phase of sn 2014j: onset of clumping as the source of recombination |
ultraluminous x-ray sources (ulxs) are extragalactic x-ray emitters located off-centre of their host galaxy and with a luminosity in excess of a few 1039 erg s-1, if emitted isotropically1,2. the discovery of periodic modulation revealed that in some ulxs the accreting compact object is a neutron star3-7, indicating lu... | diffuse x-ray emission around an ultraluminous x-ray pulsar |
volatile elements are thought to have been delivered to solar system terrestrial planets late in their formation through accretion of chondritic meteorites. mars can provide information on inner solar system volatile delivery during the earliest planet formation stages. we measured krypton isotopes in the martian meteo... | krypton in the chassigny meteorite shows mars accreted chondritic volatiles before nebular gases |
we measured the nickel isotope composition of troilites from chondritic meteorites using the nanosims to put constraints on the abundance of iron-60 in the early solar system. the troilites were selected from petrologic type 3 ordinary and carbonaceous chondrites. based on petrographic observations and mineral chemistr... | iron-60 in the early solar system revisited: insights from in situ isotope analysis of chondritic troilite |
we present new chandra and xmm-newton observations of a sample of eight radio-quiet (rq) γ-ray pulsars detected by the fermi large area telescope. for all eight pulsars we identify the x-ray counterpart, based on the x-ray source localization and the best position obtained from γ-ray pulsar timing. for psr j2030+4415 w... | radio-quiet and radio-loud pulsars: similar in gamma-rays but different in x-rays |
we present a detailed study of the stellar and orbital parameters of the post-common envelope binary central star of the planetary nebula ou 5. low-resolution spectra obtained during the primary eclipse - to our knowledge the first isolated spectra of the companion to a post-common-envelope planetary nebula central sta... | the post-common-envelope binary central star of the planetary nebula ou 5: a doubly eclipsing post-red-giant-branch system |
we present the analysis of physical conditions, chemical composition, and kinematic properties of two bow shocks - hh 529 ii and hh 529 iii - of the fully photoionized herbig-haro object hh 529 in the orion nebula. the data were obtained with the ultraviolet and visual echelle spectrograph at the 8.2m very large telesc... | photoionized herbig-haro objects in the orion nebula through deep high-spectral resolution spectroscopy - i. hh 529 ii and iii |
insights into the earliest stages of our solar system can be derived from its oldest dated solids, calcium-aluminum-rich inclusions (cais). in particular, investigating isotopic anomalies of nucleosynthetic origin in cais offers potential clues to the genetic heritage of refractory inclusions and the reservoir(s) invol... | titanium isotopic evidence for a shared genetic heritage of refractory inclusions from different carbonaceous chondrites |
context. there are known differences between the physical properties of h ii and diffuse ionized gas (dig). however, most of the studied regions in the literature are relatively bright, with log10 l(hα)[erg s−1] ≳ 37.aims: we compiled an extremely faint sample of 390 h ii regions with a median hα luminosity of 34.7 in ... | muse crowded field 3d spectroscopy in ngc 300. iii. characterizing extremely faint hii regions and diffuse ionized gas |
n103b is a type ia supernova remnant (snr) in the large magellanic cloud (lmc). we carried out new 12co(j = 3-2) and 12co(j = 1-0) observations using aste and alma. we have confirmed the existence of a giant molecular cloud at v lsr ∼ 245 km s-1 toward the southeast of the snr using aste 12co(j = 3-2) data at an angula... | molecular clouds associated with the type ia snr n103b in the large magellanic cloud |
x-ray-emitting diffuse nebulae around hot stars are observed to have soft-band temperatures in the narrow range [1-3] × 106k, independent of the stellar wind parameters and the evolutionary stage of the central star. we discuss the origin of this x-ray temperature for planetary nebulae, wolf-rayet (wr) nebulae, and int... | on the x-ray temperature of hot gas in diffuse nebulae |
we present 1 yr of optical and near-infrared photometry and spectroscopy of the type iip sne 2013k and 2013am. both objects are affected by significant extinction, due to their location in dusty regions of their respective host galaxies, eso 009-10 and ngc 3623 (m65). from the photospheric to nebular phases, these obje... | sne 2013k and 2013am: observed and physical properties of two slow, normal type iip events |
theoretical investigations suggest that magnetic fields may have played an important role in driving rapid stellar accretion rates and efficient planet formation in protoplanetary disks. experimental constraints on magnetic field strengths throughout the solar nebula can test the occurrence of magnetically driven disk ... | weak magnetic fields in the outer solar nebula recorded in cr chondrites |
in order to establish the role and expression of silicate-metal fractionation in early planetesimal bodies, we have conducted a highly siderophile element (hse: os, ir, ru, pt, pd, re) abundance and 187re-187os study of acapulcoite-lodranite meteorites. these data are reported with new petrography, mineral chemistry, b... | early metal-silicate differentiation during planetesimal formation revealed by acapulcoite and lodranite meteorites |
confronting theoretical models with observations of thermal radiation emitted by neutron stars is one of the most important ways to understand the properties of both, superdense matter in the interiors of the neutron stars and dense magnetized plasmas in their outer layers. here we review the theory of thermal emission... | neutron stars—thermal emitters |
millisecond magnetars can be formed via several channels: core collapse of massive stars, accretion-induced collapse of white dwarfs (wds), double wd mergers, double neutron star (ns) mergers, and wd-ns mergers. because the mass of ejecta from these channels could be quite different, their light curves are also expecte... | optical transients powered by magnetars: dynamics, light curves, and transition to the nebular phase |
using ukirt on mauna kea, we have carried out a new near-infrared j, h, k monitoring survey of almost a square degree of the star-forming orion nebula cluster with observations on 120 nights over three observing seasons, spanning a total of 894 days. we monitored ∼15,000 stars down to j≈ 20 using the wfcam instrument, ... | near-infrared variability in the orion nebula cluster |
in this paper, we describe integral field spectroscopic observations of four southern galactic planetary nebulae (pne), m3-4, m3-6, hen2-29 and hen2-37 covering the spectral range 3400-7000 å. we derive the ionization structure, the physical conditions, the chemical compositions and the kinematical characteristics of t... | ifu spectroscopy of southern planetary nebulae - iii |
atomic data are an important source of systematic uncertainty in our determinations of nebular chemical abundances. however, we do not have good estimates of these uncertainties since it is very difficult to assess the accuracy of the atomic data involved in the calculations. we explore here the size of these uncertain... | the impact of atomic data selection on nebular abundance determinations |
context. the nearby orion kleinmann-low nebula is one of the most prolific sources of molecular line emission. it has served as a benchmark for spectral line searches throughout the (sub)millimeter regime.aims: the main goal is to systematically study the spectral characteristics of orion kl in the λ ~ 1.3 cm band.meth... | a 1.3 cm line survey toward orion kl |
the first direct detections of gravitational waves (gws) from black hole (bh) mergers, gw 150914, gw 151226 and lvt 151012, give a robust lower limit {∼ } 70 000^{+170 000}_{-61 000} on the number of merged, highly spinning bhs in our galaxy. the total spin energy is comparable to all the kinetic energy of supernovae t... | gw 150914-like black holes as galactic high-energy sources |
we characterize the accuracy of linear-polarization mosaics made using the atacama large millimeter/submillimeter array (alma). first, we observed the bright, highly linearly polarized blazar 3c 279 at bands 3, 5, 6, and 7 (3 mm, 1.6 mm, 1.3 mm, and 0.87 mm, respectively). at each band, we measured the blazar's polariz... | characterizing the accuracy of alma linear-polarization mosaics |
we present the first linear-polarization mosaicked observations performed by the atacama large millimeter/submillimeter array (alma). we mapped the orion-kleinmann-low (orion-kl) nebula using super-sampled mosaics at 3.1 and 1.3 mm as part of the alma extension and optimization of capabilities program. we derive the ma... | the explosion in orion-kl as seen by mosaicking the magnetic field with alma |
we use a sample of 706 galaxies, selected as [o ii]λ3727 ([o ii]) emitters in the survey for high-z absorption red and dead sources (shards) on the candels/goods-n field, to study the differential attenuation of the nebular emission with respect to the stellar continuum. the sample includes only galaxies with a counter... | differential attenuation in star-forming galaxies at 0.3 ≲ z ≲ 1.5 in the shards/candels field |
blue large-amplitude pulsators (blaps) are a relatively new class of blue variable stars showing periodic variations in their light curves with periods shorter than a few tens of minutes and amplitudes of more than 10 per cent. we report nine blue variable stars identified in the omegawhite survey conducted using eso's... | the omegawhite survey for short-period variable stars - vii. high amplitude short-period blue variables |
aims: temperature uncertainties plague our understanding of abundance variations within the interstellar medium. using the phangs-muse large program, we develop and apply a new technique to model the strong emission lines arising from h ii regions in 19 nearby spiral galaxies at ~50 pc resolution and infer electron tem... | a physically motivated "charge-exchange method" for measuring electron temperatures within h ii regions |
incremental particle growth in turbulent protoplanetary nebulae is limited by a combination of barriers that can slow or stall growth. moreover, particles that grow massive enough to decouple from the gas are subject to inward radial drift, which could lead to the depletion of most disk solids before planetesimals can ... | global modeling of nebulae with particle growth, drift, and evaporation fronts. ii. the influence of porosity on solids evolution |
we present the results of an extensive observational campaign on the nearby type ibn sn 2015g, including data from radio through ultraviolet wavelengths. sn 2015g was asymmetric, showing late-time nebular lines redshifted by ∼1000 km s-1. it shared many features with the prototypical sn ibn 2006jc, including extremely ... | the nearby type ibn supernova 2015g: signatures of asymmetry and progenitor constraints |
we present an astrometric and photometric wide-field study of the galactic open star cluster m37 (ngc 2099). the studied field was observed with ground-based images covering a region of about four square degrees in the sloan-like filters ugi. we exploited the gaia catalogue to calibrate the geometric distortion of the ... | astro-photometric study of m37 with gaia and wide-field ugi-imaging |
paris is the least aqueously altered cm chondrite identified to date, classified as subtype 2.7; however, literature data indicate that some regions of this apparently brecciated meteorite may be subtype 2.9. the suite of cais in paris includes 19% spinel-pyroxene inclusions, 19% spinel inclusions, 8% spinel-pyroxene-o... | an american on paris: extent of aqueous alteration of a cm chondrite and the petrography of its refractory and amoeboid olivine inclusions |
a prediction of the classic active galactic nucleus (agn) unification model is the presence of ionization cones with different orientations depending on the agn type. confirmations of this model exist for present times, but it is less clear in the early universe. here, we use the morphology of giant ly α nebulae around... | probing the agn unification model at redshift z ∼ 3 with muse observations of giant ly α nebulae |
we present the results of a calculation of recombination coefficients for o2++ e- using an intermediate coupling treatment that fully accounts for the dependence of the distribution of population among the ground levels of o2+ on electron density and temperature. the calculation is extended down to low electron tempera... | recombination coefficients for o ii lines in nebular conditions |
current models predict that binary interactions are a major ingredient in the formation of bipolar planetary nebulae (pne) and pre-planetary nebulae (ppne). despite years of radial velocity (rv) monitoring, the paucity of known binaries amongst the latter systems means data are insufficient to examine this relationship... | the binary central star of the bipolar pre-planetary nebula iras 08005-2356 (v510 pup) |
van der waals (vdw) heterostructures have recently been introduced as versatile building blocks for a variety of novel nanoscale and quantum technologies. harnessing the unique properties of these heterostructures requires a deep understanding of the involved interfacial interactions and a meticulous control of the gro... | dynamics of antimonene–graphene van der waals growth |
we have found two refractory inclusions in the co3.00 carbonaceous chondrite dominion range (dom) 08006 that appear to be primary condensates from the early solar nebula. one, inclusion 56-1, contains the first four phases predicted to form by equilibrium gas-solid condensation: corundum; hibonite; grossite; and perovs... | condensate refractory inclusions from the co3.00 chondrite dominion range 08006: petrography, mineral chemistry, and isotopic compositions |
the relatively nearby spiral galaxy ngc 6946 is one of the most actively star-forming galaxies in the local universe. ten supernovae (sne) have been observed since 1917, and hence ngc 6946 surely contains a large number of supernova remnants (snrs). here we report a new optical search for these snrs using narrowband im... | a new, larger sample of supernova remnants in ngc 6946 |
ofek identified first j141918.9+394036 (hereafter first j1419+3940) as a radio source sharing similar properties and host galaxy type to the compact, persistent radio source associated with the first known repeating fast radio burst, frb 121102. law et al. showed that first j1419+3940 is a transient source decaying in ... | resolving the decades-long transient first j141918.9+394036: an orphan long gamma-ray burst or a young magnetar nebula? |
the primary goal of this paper is to make a direct comparison between the measured and model-predicted abundances of he, c, and n in a sample of 35 well-observed galactic planetary nebulae (pne). all observations, data reductions, and abundance determinations were performed in house to ensure maximum homogeneity. proge... | on the production of he, c, and n by low- and intermediate-mass stars: a comparison of observed and model-predicted planetary nebula abundances |
a prediction of the current paradigm of the hierarchical assembly of galaxies is the presence of supermassive dual black holes at separations of a few kpc or less. in this context, we report the detection of a narrow-line emitter within the extended lyα nebula ( 120 kpc diameter) of the luminous radio-quiet quasi-stell... | discovery of a dual agn at z ≃ 3.3 with 20 kpc separation |
current planet formation theories provide successful frameworks with which to interpret the array of new observational data in this field. however, each of the two main theories (core accretion, gravitational instability) is unable to explain some key aspects. in many planet formation calculations, it is usual to treat... | the maximum mass solar nebula and the early formation of planets |
massive stars play an important role in both cluster and galactic evolution and the rate at which they lose mass is a key driver of both their own evolution and their interaction with the environment up to and including their terminal sne explosions. young massive clusters provide an ideal opportunity to study a co-eva... | an alma 3 mm continuum census of westerlund 1 |
previous analyses of the spectra of ob-type stars in the magellanic clouds have identified targets with low projected rotational velocities and relatively high nitrogen abundances; the evolutionary status of these objects remains unclear. the vlt-flames tarantula survey obtained spectroscopy for over 800 early-type sta... | the vlt-flames tarantula survey. xxviii. nitrogen abundances for apparently single dwarf and giant b-type stars with small projected rotational velocities |
we present continuum and molecular line emission alma observations of oh 231.8+4.2, a well studied bipolar nebula around an asymptotic giant branch (agb) star. the high-angular resolution ( 0.''2-0.''3) and sensitivity of our alma maps provide the most detailed and accurate description of the overall nebular structure ... | through the magnifying glass: alma acute viewing of the intricate nebular architecture of oh 231.8+4.2 |
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