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supermassive black hole (bh) mergers produce powerful gravitational wave emission. asymmetry in this emission imparts a recoil kick to the merged bh, which can eject the bh from its host galaxy altogether. recoiling bhs could be observed as offset active galactic nuclei (agn). several candidates have been identified, b... | recoiling black holes: prospects for detection and implications of spin alignment |
collisions were suggested to potentially play a role in the formation of massive stars in present day clusters, and have likely been relevant during the formation of massive stars and intermediate mass black holes within the first star clusters. in the early universe, the first stellar clusters were particularly dense,... | collisions in primordial star clusters. formation pathway for intermediate mass black holes |
we present new constraints on parameters of cosmic dawn and the epoch of reionization derived from the edges high-band spectrum (90-190 mhz). the parameters are probed by evaluating global 21 cm signals generated with the recently developed global21cm tool. this tool uses neural networks trained and tested on ∼30,000 s... | results from edges high-band. iii. new constraints on parameters of the early universe |
we have reprocessed over 100 terabytes of single-exposure wide-field infrared survey explorer (wise)/neowise images to create the deepest ever full-sky maps at 3-5 microns. we include all publicly available w1 and w2 imaging—a total of ∼8 million exposures in each band—from ∼37 months of observations spanning 2010 janu... | deep full-sky coadds from three years of wise and neowise observations |
using hubble space telescope cosmic origins spectrograph observations of 89 qso sightlines through the sloan digital sky survey footprint, we study the relationships between c iv absorption systems and the properties of nearby galaxies, as well as the large-scale environment. to maintain sensitivity to very faint galax... | a deep search for faint galaxies associated with very low redshift c iv absorbers. iii. the mass- and environment-dependent circumgalactic medium |
we use new precision measurements of black hole (bh) masses from water megamaser disks to investigate scaling relations between macroscopic galaxy properties and supermassive bh mass. the megamaser-derived bh masses span 106-108 {m}⊙ , while all the galaxy properties that we examine (including total stellar mass, centr... | megamaser disks reveal a broad distribution of black hole mass in spiral galaxies |
we present the lyman α flux power spectrum measurements of the xq-100 sample of quasar spectra obtained in the context of the european southern observatory large programme 'quasars and their absorption lines: a legacy survey of the high redshift universe with vlt/xshooter'. using 100 quasar spectra with medium resoluti... | the lyman α forest power spectrum from the xq-100 legacy survey |
we present an analysis of uv spectra of 13 quasars believed to belong to extreme population a (xa) quasars, aimed at the estimation of the chemical abundances of the broad-line-emitting gas. metallicity estimates for the broad-line-emitting gas of quasars are subject to a number of caveats; xa sources with the stronges... | high metal content of highly accreting quasars |
accreting black holes can drive fast and energetic nuclear winds that may be an important feedback mechanism associated with active galactic nuclei (agn). in this paper, we implement a scheme for capturing feedback from these fast nuclear winds and examine their impact in simulations of isolated disc galaxies. stellar ... | the impact of agn wind feedback in simulations of isolated galaxies with a multiphase ism |
the extended baryon oscillation spectroscopic survey of the sloan digital sky survey (sdss-iv/eboss) has an extensive quasar program that combines several selection methods. among these, the photometric variability technique provides highly uniform samples, which are unaffected by the redshift bias of traditional optic... | the extended baryon oscillation spectroscopic survey: variability selection and quasar luminosity function |
while low-mass, star-forming galaxies are often considered as the primary driver of reionization, their actual contribution to the cosmic ultraviolet background is still uncertain, mostly because the escape fraction of ionizing photons is only poorly constrained. theoretical studies have shown that efficient supernova ... | escape of ionizing radiation from high-redshift dwarf galaxies: role of agn feedback |
we investigate extremely red quasars (erqs), a remarkable population of heavily reddened quasars at redshift z ∼ 2-3 that might be caught during a short-lived `blow-out' phase of quasar/galaxy evolution. we perform a near-ir observational campaign using keck/nirspec, vlt/x-shooter, and gemini/gnirs to measure rest-fram... | erqs are the boss of quasar samples: the highest velocity [o iii] quasar outflows |
we present a science forecast for the extended baryon oscillation spectroscopic survey (eboss) survey. focusing on discrete tracers, we forecast the expected accuracy of the baryonic acoustic oscillation (bao), the redshift-space distortion (rsd) measurements, the fnl parameter quantifying the primordial non-gaussianit... | the extended baryon oscillation spectroscopic survey: a cosmological forecast |
we report high spatial resolution (∼0.″076, 410 pc) atacama large millimeter/submillimeter array imaging of the dust continuum and the ionized carbon line [c ii] in a luminous quasar host galaxy at z = 6.6, 800 million years after the big bang. based on previous studies, this galaxy hosts a ∼1 × 109 {m}⊙black hole and ... | 400 pc imaging of a massive quasar host galaxy at a redshift of 6.6 |
recently, the ligo-virgo collaboration (lvc) has concluded there is no evidence for lensed gravitational waves (gws) in the first half of the o3 run [ligo scientific collaboration and virgo collaboration, search for lensing signatures in the gravitational-wave observations from the first half of ligo-virgo's third obse... | evidence for lensing of gravitational waves from ligo-virgo data |
we present the discovery of one or two extremely faint z ~ 6 quasars in 6.5 deg2 utilizing a unique capability of the wide-field imaging of the subaru/suprime-cam. the quasar selection was made in (i'-zb ) and (zb -zr ) colors, where zb and zr are bandpasses with central wavelengths of 8842 å and 9841 å, respectively. ... | the subaru high-z quasar survey: discovery of faint z ~ 6 quasars |
we present a systematic analysis of x-ray archival data of all the 29 quasars (qsos) at z> 5.5 observed so far with chandra, xmm-newton and swift-xrt, including the most-distant quasar ever discovered, ulas j1120+0641 (z = 7.08). this study allows us to place constraints on the mean spectral properties of the primor... | the x-ray properties of z 6 luminous quasars |
the second data release of gaia revealed a parallax zero-point offset of −0.029 mas based on quasars. the value depended on the position on the sky, and also likely on magnitude and colour. the offset and its dependence on other parameters inhibited improvement in the local distance scale using for example the cepheid ... | the parallax zero-point offset from gaia edr3 data |
we investigate the mean star formation rates (sfrs) in the host galaxies of ∼3000 optically selected quasi-stellar objects (qsos) from the sloan digital sky survey within the herschel-atlas fields, and a radio-luminous subsample covering the redshift range of z = 0.2-2.5. using wide-field infrared survey explorer (wise... | the mean star formation rates of unobscured qsos: searching for evidence of suppressed or enhanced star formation |
distortions of the observed cosmic microwave background provide a direct measurement of the microwave background temperature at redshifts from 0 to 1 (refs. 1,2). some additional background temperature estimates exist at redshifts from 1.8 to 3.3 based on molecular and atomic line-excitation temperatures in quasar abso... | microwave background temperature at a redshift of 6.34 from h2o absorption |
a tight non-linear relation between the x-ray and the optical-ultraviolet (uv) emission has been observed in active galactic nuclei (agn) over a wide range of redshift and several orders of magnitude in luminosity, suggesting the existence of an ubiquitous physical mechanism regulating the energy transfer between the a... | quasars as standard candles ii. the non-linear relation between uv and x-ray emission at high redshifts |
we report the results of 1.‧5 × 3‧ mapping at 1.1 mm with the atacama large millimeter/submillimeter array toward the central region of the z = 3.09 ssa22 protocluster. by combining our source catalog with archival spectroscopic redshifts, we find that eight submillimeter galaxies (smgs) with flux densities, s1.1 mm = ... | alma deep field in ssa22: a concentration of dusty starbursts in a z = 3.09 protocluster core |
giant lobes of plasma extend ≈55° above and below the galactic center, glowing in emission from gamma rays (the fermi bubbles) to microwaves and polarized radio waves. we use ultraviolet absorption-line spectra from the hubble space telescope to constrain the velocity of the outflowing gas within these regions, targeti... | probing the fermi bubbles in ultraviolet absorption: a spectroscopic signature of the milky way's biconical nuclear outflow |
we performed a survey of the x-ray properties of 41 objects from the wise/sdss selected hyper-luminous (wissh) quasars sample, which includes 86 broad-line quasars with bolometric luminosity lbol ≳ 2 × 1047 erg s-1 shining at z 2-4. we used both proprietary and archival chandra and xmm-newton observations. twenty-one q... | the wissh quasars project. iii. x-ray properties of hyper-luminous quasars |
we present alma band 3 observations of the co(6-5), co(7-6), and [c i] 369 μm emission lines in three of the highest-redshift quasar host galaxies at 6.6< z< 6.9. these measurements constitute the highest-redshift co detections to date. the target quasars have previously been detected in [c ii] 158 μm emission an... | molecular gas in three z ∼ 7 quasar host galaxies |
we develop a model of bose-einstein condensate dark matter halos with a solitonic core and an isothermal atmosphere based on a generalized gross-pitaevskii equation [p. h. chavanis, eur. phys. j. plus 132, 248 (2017), 10.1140/epjp/i2017-11544-3]. this equation provides a heuristic coarse-grained parametrization of the ... | predictive model of bec dark matter halos with a solitonic core and an isothermal atmosphere |
we describe the scientific goals and survey design of the first large absorption survey in h i (flash), a wide field survey for 21-cm line absorption in neutral atomic hydrogen (h i) at intermediate cosmological redshifts. flash will be carried out with the australian square kilometre array pathfinder (askap) radio tel... | the first large absorption survey in h i (flash): i. science goals and survey design |
the nature of dark matter is one of the most important unsolved questions in science. some darkf matter candidates do not have sufficient nongravitational interactions to be probed in laboratory or accelerator experiments. it is thus important to develop astrophysical probes which can constrain or lead to a discovery o... | constraints on sterile neutrino models from strong gravitational lensing, milky way satellites, and the lyman-α forest |
we present a survey for metal absorption systems traced by neutral oxygen over 3.2 < z < 6.5. our survey uses keck/esi and vlt/x-shooter spectra of 199 qsos with redshifts up to 6.6. in total, we detect 74 o i absorbers, of which 57 are separated from the background qso by more than 5000 km s-1. we use a maximum ... | the evolution of o i over 3.2 < z < 6.5: reionization of the circumgalactic medium |
the detection of two z ~ 13 galaxy candidates has opened a new window on galaxy formation at an era only 330 myr after the big bang. here, we investigate the physical nature of these sources: are we witnessing star forming galaxies or quasars at such early epochs? if powered by star formation, the observed ultraviolet ... | are the newly-discovered z 13 drop-out sources starburst galaxies or quasars? |
the filamentary network of intergalactic medium (igm) gas that gives origin to the lyα forest in the spectra of distant quasars encodes information on the physics of structure formation and the early thermodynamics of diffuse baryonic material. here we use a massive suite of more than 400 high-resolution cosmological h... | inferring the thermal history of the intergalactic medium from the properties of the hydrogen and helium lyα forest |
we present a centennial review of the history of the term known as the cosmological constant. first introduced to the general theory of relativity by einstein in 1917 in order to describe a universe that was assumed to be static, the term fell from favour in the wake of the discovery of the expanding universe, only to ... | one hundred years of the cosmological constant: from "superfluous stunt" to dark energy |
we investigate the observed correlation between the 2-10 kev x-ray luminosity (in unit of the eddington luminosity; lx ≡ lx/ledd) and the photon index (γ) of the x-ray spectrum for both black hole x-ray binaries (bhbs) and active galactic nuclei (agns). we construct a large sample, with 10- 9 ≲ lx ≲ 10- 1. we find that... | correlation between the photon index and x-ray luminosity of black hole x-ray binaries and active galactic nuclei: observations and interpretation |
recent observations with alma have revealed evidence for nonthermal synchrotron emission from the core regions of two nearby seyfert galaxies. this suggests that the coronae of accretion disks in active galactic nuclei (agns) can be conducive to the acceleration of nonthermal electrons, in addition to the hot, thermal ... | on high-energy particles in accretion disk coronae of supermassive black holes: implications for mev gamma-rays and high-energy neutrinos from agn cores |
we have started a long-term reverberation mapping (rm) project using the wyoming infrared observatory 2.3 m telescope titled “monitoring agns with hβ asymmetry” (maha). the motivations of the project are to explore the geometry and kinematics of the gas responsible for complex hβ emission-line profiles, ideally leading... | monitoring agns with hβ asymmetry. i. first results: velocity-resolved reverberation mapping |
the supermassive black holes originally in the nuclei of two merging galaxies will form a binary in the remnant core. the early evolution of the massive binary is driven by dynamical friction before the binary becomes “hard” and eventually reaches coalescence through gravitational-wave emission. we consider the dynamic... | dynamical friction and the evolution of supermassive black hole binaries: the final hundred-parsec problem |
the rapid assembly of the massive black holes that power the luminous quasars observed at z ∼ 6-7 remains a puzzle. various direct collapse models have been proposed to head-start black hole growth from initial seeds with masses ∼105 m⊙, which can then reach a billion solar mass while accreting at the eddington limit. ... | growing massive black holes through supercritical accretion of stellar-mass seeds |
we investigate the coevolution of galaxies and hosted supermassive black holes (bhs) throughout the history of the universe by a statistical approach based on the continuity equation and the abundance matching technique. specifically, we present analytical solutions of the continuity equation without source terms to re... | black hole and galaxy coevolution from continuity equation and abundance matching |
we present host stellar velocity dispersion measurements for a sample of 88 broad-line quasars at 0.1\lt z\lt 1 (46 at z\gt 0.6) from the sloan digital sky survey reverberation mapping (sdss-rm) project. high signal-to-noise ratio coadded spectra (average s/n≈ 30 per 69 km {{s}-1} pixel) from sdss-rm allowed for the de... | the sloan digital sky survey reverberation mapping project: no evidence for evolution in the m• -σ* relation to z∼ 1 |
we present deep (9 hr) gemini-n/gemini near-infrared spectrograph near-infrared spectroscopic observations of ulas j1342+0928, a luminous quasar at z = 7.54. various broad emission lines were detected, as well as the underlying continuum and iron forests over the rest-frame wavelength 970-2930 å. there is a clear trend... | no redshift evolution in the broad-line-region metallicity up to z = 7.54: deep near-infrared spectroscopy of ulas j1342+0928 |
in this paper, based on a 2.29 ghz vlbi all-sky survey of 613 milliarcsecond ultra-compact radio sources with 0.0035<z<3.787, we describe a method of identifying the sub-sample which can serve as individual standard rulers in cosmology. if the linear size of the compact structure is assumed to depend on source lu... | measuring the speed of light with ultra-compact radio quasars |
the multiwavelength spectral and temporal variability observed in blazars set tight constraints on current theoretical emission models. here, we investigate the relativistic magnetic reconnection process as a source of blazar emission in which quasi-spherical plasmoids, containing relativistic particles and magnetic fi... | radiative signatures of plasmoid-dominated reconnection in blazar jets |
a major goal of the atacama large millimeter/submillimeter array (alma) is to make accurate images with resolutions of tens of milliarcseconds, which at submillimeter (submm) wavelengths requires baselines up to ∼15 km. to develop and test this capability, a long baseline campaign (lbc) was carried out from 2014 septem... | the 2014 alma long baseline campaign: an overview |
given a galaxy's stellar mass, its host halo mass has a lower limit from the cosmic baryon fraction and known baryonic physics. at z> 4, galaxy stellar mass functions place lower limits on halo number densities that approach expected lambda cold dark matter halo mass functions. high-redshift galaxy stellar mass func... | the most massive galaxies and black holes allowed by λcdm |
we present a study exploring the nature and properties of the circumgalactic medium (cgm) and its connection to the atomic gas content in the interstellar medium (ism) of galaxies as traced by the h i 21 cm line. our sample includes 45 low-z (0.026-0.049) galaxies from the galex arecibo sdss survey (galaxy evolution ex... | connection between the circumgalactic medium and the interstellar medium of galaxies: results from the cos-gass survey |
using chandra observations in the 2.15 deg2 cosmos-legacy field, we present one of the most accurate measurements of the cosmic x-ray background (cxb) spectrum to date in the [0.3-7] kev energy band. the cxb has three distinct components: contributions from two galactic collisional thermal plasmas at kt ∼ 0.27 and 0.07... | the chandra cosmos legacy survey: energy spectrum of the cosmic x-ray background and constraints on undetected populations |
we present the first results from the quasar feedback survey, a sample of 42 z < 0.2, [o iii] luminous agns ( l[o iii] > 1042.1 ergs s-1) with moderate radio luminosities (i.e. l1.4ghz > 1023.4 w hz-1; median l1.4ghz = 5.9 × 1023 w hz-1). using high spatial resolution (~0.3-1 arcsec), 1.5-6 ghz radio images fr... | the quasar feedback survey: discovering hidden radio-agn and their connection to the host galaxy ionized gas |
we revisit the dependence of the covering factor (cf) of dust torus on physical properties of active galactic nuclei (agns) by taking into account an agn polar dust emission. the cf is converted from a ratio of infrared (ir) luminosity contributed from agn dust torus ( ${l}_{\mathrm{ir}}^{\mathrm{torus}}$ ) and agn bol... | how does the polar dust affect the correlation between dust covering factor and eddington ratio in type 1 quasars selected from the sloan digital sky survey data release 16? |
we consider the cosmological consequences if a small fraction (f≲ 0.1) of the dark matter is ultra-strongly self-interacting, with an elastic self-interaction cross section per unit mass σ \gg 1 c{{m}2} {{g}-1}. this possibility evades all current constraints that assume that the self-interacting component makes up the... | supermassive black holes from ultra-strongly self-interacting dark matter |
dust plays an important role in our understanding of the universe, but it is not obvious yet how the dust in the distant universe was formed. i derived the dust yields per asymptotic giant branch (agb) star and per supernova (sn) required to explain dust masses of galaxies at z = 6.3-7.5 (680-850 million years after th... | dust production 680-850 million years after the big bang |
black hole masses are crucial to understanding the physics of the connection between quasars and their host galaxies and measuring cosmic black hole-growth. at high redshift, z ≳ 2.1, black hole masses are normally derived using the velocity width of the c iv λ λ1548, 1550 broad emission line, based on the assumption t... | c iv emission-line properties and systematic trends in quasar black hole mass estimates |
the advent of time domain astronomy is revolutionizing our understanding of the universe. programs such as the catalina real-time transient survey (crts) or the palomar transient factory (ptf) surveyed millions of objects for several years, allowing variability studies on large statistical samples. the inspection of ≈2... | testing the binary hypothesis: pulsar timing constraints on supermassive black hole binary candidates |
using few-body simulations, we investigate the evolution of supermassive black holes (smbhs) in galaxies (m* = 1010-1012 m⊙ at z = 0) at 0 < z < 4. following galaxy merger trees from the millennium simulation, we model bh mergers with two extreme binary decay scenarios for the 'hard binary' stage: a full or an em... | interactions between multiple supermassive black holes in galactic nuclei: a solution to the final parsec problem |
this is the eighth in a series of papers reporting on a large reverberation mapping (rm) campaign to measure black hole (bh) mass in active galactic nuclei with high accretion rates. we employ the recently developed dynamical modeling approach for broad-line regions (blrs) based on the method of pancoast et al. to anal... | supermassive black holes with high accretion rates in active galactic nuclei. viii. structure of the broad-line region and mass of the central black hole in mrk 142 |
cmb lensing tomography, or the cross-correlation between cmb lensing maps and large-scale structure tracers over a well-defined redshift range, has the potential to map the amplitude and growth of structure over cosmic time, provide some of the most stringent tests of gravity, and break important degeneracies between c... | unwise tomography of planck cmb lensing |
we present a study of optical, uv and x-ray light curves of the nearby changing look active galactic nucleus in the galaxy ngc 1566 obtained with the neil gehrels swift observatory and the master global robotic network over the period 2007-2018. we also report on our optical spectroscopy at the south african astronomic... | new changing look case in ngc 1566 |
we have recently identified a substantial number of type 1 active galactic nuclei (agns) featuring weak broad-line regions (blrs) at z\lt 0.2 from detailed analysis of galaxy spectra in the sloan digital sky survey data release 7. these objects predominantly show a stellar continuum but also a broad hα emission line, i... | a new catalog of type 1 agns and its implications on the agn unified model |
the current hierarchical merging paradigm and λcdm predict that the z∼ 4-8 universe should be a time in which the most massive galaxies are transitioning from their initial halo assembly to the later baryonic evolution seen in star-forming galaxies and quasars. however, no evidence of this transition has been found in ... | the impossibly early galaxy problem |
radio emission from radio-quiet quasars may be due to star formation in the quasar host galaxy, to a jet launched by the supermassive black hole, or to relativistic particles accelerated in a wide-angle radiatively driven outflow. in this paper, we examine whether radio emission from radio-quiet quasars is a byproduct ... | star formation in quasar hosts and the origin of radio emission in radio-quiet quasars |
mse is an 11.25m aperture observatory with a 1.5 square degree field of view that will be fully dedicated to multi-object spectroscopy. more than 3200 fibres will feed spectrographs operating at low (r ~ 2000 - 3500) and moderate (r ~ 6000) spectral resolution, and approximately 1000 fibers will feed spectrographs oper... | the detailed science case for the maunakea spectroscopic explorer: the composition and dynamics of the faint universe |
the circumgalactic medium (cgm) encodes signatures of the galaxy-formation process, including the interaction of galactic outflows driven by stellar and supermassive black hole (smbh) feedback with the gaseous halo. moving beyond spherically symmetric radial profiles, we study the angular dependence of cgm properties a... | predictions for anisotropic x-ray signatures in the circumgalactic medium: imprints of supermassive black hole driven outflows |
we investigate the large-scale clustering of the final spectroscopic sample of quasars from the recently completed extended baryon oscillation spectroscopic survey (eboss). the sample contains 343 708 objects in the redshift range 0.8 < z < 2.2 and 72 667 objects with redshifts 2.2 < z < 3.5, covering an ef... | primordial non-gaussianity from the completed sdss-iv extended baryon oscillation spectroscopic survey - i: catalogue preparation and systematic mitigation |
we study the distribution and evolution of highly ionized intergalactic metals in the evolution and assembly of galaxies and their environment (eagle) cosmological, hydrodynamical simulations. eagle has been shown to reproduce a wide range of galaxy properties while its subgrid feedback was calibrated without consideri... | cosmic distribution of highly ionized metals and their physical conditions in the eagle simulations |
we construct a new analytic phenomenological model for the extended circumgalactic material (cgm) of l* galaxies. our model reproduces the o vii/o viii absorption observations of the milky way (mw) and the o vi measurements reported by the cos-halos and ecgm surveys. the warm/hot gas is in hydrostatic equilibrium in an... | massive warm/hot galaxy coronae. ii. isentropic model |
quasar proximity zones at $z\gt 5.5$ correspond to overdense and overionized environments. galaxies found inside proximity zones can therefore display features that would otherwise be masked by absorption in the intergalactic medium. we demonstrate the utility of this quasar-galaxy synergy by reporting the discovery of... | three lyα emitting galaxies within a quasar proximity zone at z ∼ 5.8 |
we use a background quasar to detect the presence of circumgalactic gas around a z=0.91 low-mass star-forming galaxy. data from the new multi unit spectroscopic explorer (muse) on the very large telescope show that the galaxy has a dust-corrected star formation rate (sfr) of 4.7 ± 2.0 m⊙ yr-1, with no companion down to... | possible signatures of a cold-flow disk from muse using a z ∼ 1 galaxy-quasar pair toward sdss j1422-0001 |
previous studies have shown that wide-field infrared survey explorer-selected hyperluminous, hot dust-obscured galaxies (hot dogs) are powered by highly dust-obscured, possibly compton-thick active galactic nuclei (agns). high obscuration provides us a good chance to study the host morphology of the most luminous agns ... | the most luminous heavily obscured quasars have a high merger fraction: morphological study of wise-selected hot dust-obscured galaxies |
an observational tension on estimates of the hubble parameter, h0, using early and late universe information, is being of intense discussion in the literature. additionally, it is of great importance to measure h0 independently of cmb data and local distance ladder method. in this sense, we analyze 15 measurements of t... | bao signatures in the 2-point angular correlations and the hubble tension |
we describe the execution and data reduction of the european southern observatory large programme "quasars and their absorption lines: a legacy survey of the high-redshift universe with vlt/x-shooter" (hereafter "xq-100"). xq-100 has produced and made publicly available a homogeneous and high-quality sample of echelle ... | xq-100: a legacy survey of one hundred 3.5 ≲ z ≲ 4.5 quasars observed with vlt/x-shooter |
we investigate the dependence of black hole accretion rate (bhar) on host-galaxy star formation rate (sfr) and stellar mass (m *) in the candels/goods-south field in the redshift range of 0.5≤slant z< 2.0. our sample consists of ≈ {{18,000}} galaxies, allowing us to probe galaxies with 0.1{m}⊙ {{yr}}-1≲ {sfr}≲ 100 {... | black hole growth is mainly linked to host-galaxy stellar mass rather than star formation rate |
using ≈190 000 spectra from the 17th data release of the sloan digital sky survey (sdss), we investigate the ultraviolet emission line properties in z ≈ 2 quasars. specifically, we quantify how the shape of c iv λ1549 and the equivalent width (ew) of he ii λ1640 depend on the black hole mass and eddington ratio inferre... | testing agn outflow and accretion models with c iv and he ii emission line demographics in z ≈ 2 quasars |
in order to investigate the impact of radio jets on the interstellar medium (ism) of galaxies hosting active galactic nuclei (agn), we present subarcsecond-resolution atacama large millimeter/submillimeter array (alma) co(2-1) and co(3-2) observations of the teacup galaxy. this is a nearby (dl = 388 mpc) radio-quiet ty... | jet-induced molecular gas excitation and turbulence in the teacup |
we provide predictions of the yield of 7 < z < 9 quasars from the euclid wide survey, updating the calculation presented in the euclid red book in several ways. we account for revisions to the euclid near-infrared filter wavelengths; we adopt steeper rates of decline of the quasar luminosity function (qlf; φ) wit... | euclid preparation. v. predicted yield of redshift 7 < z < 9 quasars from the wide survey |
hydrodynamical simulations are increasingly able to accurately model physical systems on stellar, galactic, and cosmological scales; however, the utility of these simulations is often limited by our ability to directly compare them with the data sets produced by observers: spectra, photometry, etc. to address this prob... | trident: a universal tool for generating synthetic absorption spectra from astrophysical simulations |
we compare the constraints from two (2019 and 2021) compilations of h ii starburst galaxy (h iig) data and test the model independence of quasar (qso) angular size data using six spatially flat and non-flat cosmological models. we find that the new 2021 compilation of h iig data generally provides tighter constraints a... | cosmological constraints from h ii starburst galaxy, quasar angular size, and other measurements |
both theory and observations suggest that outflows driven by an active central supermassive black hole have a feedback effect on shaping the global properties of the host galaxy1-8. however, whether feedback from the outflow is effective, and if so, whether it is positive or negative, have long been controversial. here... | evidence for the connection between star formation rate and the evolutionary phases of quasars |
the quest for high-redshift quasars has led to a series of record-breaking sources, with the current record holder at z = 7.642. here, we show how future detections of z > 8 quasars impact the constraints on the parameters for black hole growth and seed models. using broad flat priors on the growth parameters (eddin... | the search for the farthest quasar: consequences for black hole growth and seed models |
we report the first results of a high-redshift (z ≳ 5) quasar survey using the dark energy spectroscopic instrument (desi). as a desi secondary target program, this survey is designed to carry out a systematic search and investigation of quasars at 4.8 < z < 6.8. the target selection is based on the desi legacy i... | desi z ≳ 5 quasar survey. i. a first sample of 400 new quasars at z 4.7-6.6 |
supermassive black holes weighing up to ∼109 m ⊙ are in place by z ∼ 7, when the age of the universe is ≲1 gyr. this implies a time crunch for their growth, since such high masses cannot be easily reached in standard accretion scenarios. here, we explore the physical conditions that would lead to optimal growth wherein... | conditions for optimal growth of black hole seeds |
past x-ray observations of the nearby luminous quasar pds 456 (at z = 0.184) have revealed a wide-angle accretion disk wind with an outflow velocity of ∼-0.25c, as observed through observations of its blueshifted iron k-shell absorption line profile. here we present three new xmm-newton observations of pds 456: one in ... | resolving the soft x-ray ultrafast outflow in pds 456 |
this is the third in a series of papers reporting on a large reverberation-mapping campaign aimed to study the properties of active galactic nuclei (agns) with high accretion rates. we present new results on the variability of the optical fe ii emission lines in 10 agns observed by the yunnan observatory 2.4 m telescop... | supermassive black holes with high accretion rates in active galactic nuclei. iii. detection of fe ii reverberation in nine narrow-line seyfert 1 galaxies |
we present two catalogs of radio-loud candidate blazars whose wide-field infrared survey explorer (wise) mid-infrared colors are selected to be consistent with the colors of confirmed γ-ray-emitting blazars. the first catalog is the improved and expanded release of the wise blazar-like radio-loud sources (wibrals) cata... | two new catalogs of blazar candidates in the wise infrared sky |
we announce the second data release (dr2) of the noirlab source catalog (nsc), using 412,116 public images from ctio-4 m+decam, the kpno-4 m+mosaic3, and the bok-2.3 m+90prime. nsc dr2 contains over 3.9 billion unique objects, 68 billion individual source measurements, covers ≈35,000 square degrees of the sky, has dept... | second data release of the all-sky noirlab source catalog |
compact objects are expected to exist in the accretion disks of supermassive black holes (smbhs) in active galactic nuclei (agns), and in the presence of such a dense environment (∼1014 cm-3), they will form a new kind of stellar population denoted as accretion-modified stars (amss). this hypothesis is supported by rec... | accretion-modified stars in accretion disks of active galactic nuclei: slowly transient appearance |
we study the early growth of massive seed black holes (bhs) via accretion in protogalactic nuclei where the stellar bulge component is assembled, performing axisymmetric two-dimensional radiation hydrodynamical simulations. we find that when a seed bh with m • ~ 105 m ⊙ is embedded in dense metal-poor gas (z = 0.01 z ⊙... | rapid growth of seed black holes during early bulge formation |
the elemental abundances in the broad-line regions of high-redshift quasars trace the chemical evolution in the nuclear regions of massive galaxies in the early universe. in this work, we study metallicity-sensitive broad emission-line flux ratios in rest-frame uv spectra of 25 high-redshift (5.8 < z < 7.5) quasa... | chemical abundance of z ∼ 6 quasar broad-line regions in the xqr-30 sample |
we predict the observational signatures of galaxy scale outflows powered by active galactic nuclei (agn). most of the emission is produced by the forward shock driven into the ambient interstellar medium (ism) rather than by the reverse shock. agn-powered galactic winds with energetics suggested by phenomenological fee... | observational signatures of galactic winds powered by active galactic nuclei |
we present damped harmonic oscillator (dho) light-curve modeling for a sample of 12,714 spectroscopically confirmed quasars in the sloan digital sky survey stripe 82 region. dho is a second-order continuous-time autoregressive moving-average process, which can be fully described using four independent parameters: a nat... | examining agn uv/optical variability beyond the simple damped random walk |
motivated by recent measurements of the number density of faint agn at high redshift, we investigate the contribution of quasars to reionization by tracking the growth of central supermassive black holes in an update of the meraxes semi-analytic model. the model is calibrated against the observed stellar mass function ... | dark-ages reionization and galaxy formation simulation - x. the small contribution of quasars to reionization |
we present a newly discovered correlation between the wind outflow velocity and the x-ray luminosity in the luminous (lbol ∼ 1047erg s - 1) nearby (z = 0.184) quasar pds 456. all the contemporary xmm-newton, nustar and suzaku observations from 2001-2014 were revisited and we find that the centroid energy of the blueshi... | evidence for a radiatively driven disc-wind in pds 456? |
in the context of a cosmography approach to using the data of the hubble diagram for supernovae, quasars, and gamma-ray bursts, we study dark energy (de) parameterizations and the concordance cold dark matter (λcdm) universe. using different combinations of data samples including (i) supernovae (pantheon), (ii) pantheo... | a cosmography approach to dark energy cosmologies: new constraints using the hubble diagrams of supernovae, quasars, and gamma-ray bursts |
we report new observations from a systematic, spectroscopic, ultraviolet absorption-line survey that maps the spatial and kinematic properties of the high velocity gas in the galactic center (gc) region. we examine the hypothesis that this gas traces the biconical nuclear outflow. we use an ultraviolet spectra of 47 ba... | mapping the nuclear outflow of the milky way: studying the kinematics and spatial extent of the northern fermi bubble |
context. the ionizing lyman continuum flux escaping from high-redshift galaxies into the intergalactic medium is a fundamental quantity to understand the physical processes involved in the reionization epoch. however, from an observational point of view, direct detections of hi ionizing photons at high redshifts are fe... | the lyman continuum escape fraction of galaxies at z = 3.3 in the vuds-lbc/cosmos field |
quasars with extremely red infrared-to-optical colours are an interesting population that can test ideas about quasar evolution as well as orientation, obscuration and geometric effects in the so-called agn unified model. to identify such a population, we match the quasar catalogues of the sloan digital sky survey (sds... | extremely red quasars from sdss, boss and wise: classification of optical spectra |
the idea that photons can convert to axion-like particles (alps) γ → a in or around an agn and reconvert back to photons a → γ in the milky way magnetic field has been put forward in 2008 and has recently attracted growing interest. yet, so far nobody has estimated the conversion probability γ → a as carefully as allow... | photons to axion-like particles conversion in active galactic nuclei |
we present rest-frame lyα equivalent widths (ew0) of 417 lyα emitters (laes) detected with multi unit spectroscopic explorer (muse) on the very large telescope (vlt) at 2.9 <z< 6.6 in the hubble ultra deep field. based on the deep muse spectroscopy and ancillary hubble space telescope (hst) photometry data, we ca... | the muse hubble ultra deep field survey. x. lyα equivalent widths at 2.9 < z < 6.6 |
reconstruction techniques for intrinsic quasar continua are crucial for the precision study of lyman α (ly α) and lyman β (ly β) transmission at z > 5.5, where the λ < 1215 å emission of quasars is nearly completely absorbed. while the number and quality of spectroscopic observations have become theoretically suf... | a comparison of quasar emission reconstruction techniques for z ≥ 5.0 lyman α and lyman β transmission |
we use 38 c iv quasar (qso) reverberation-mapped observations, which span eight orders of magnitude in luminosity and the redshift range 0.001064 ≤ z ≤ 3.368, to simultaneously constrain cosmological-model and qso radius-luminosity (r-l) relation parameters in six cosmological models, using an improved technique that m... | standardizing reverberation-measured c iv time-lag quasars, and using them with standardized mg ii quasars to constrain cosmological parameters |
microquasars are stellar-mass black holes accreting matter from a companion star and ejecting plasma jets at almost the speed of light. they are analogues of quasars that contain supermassive black holes of 106 to 1010 solar masses. accretion in microquasars varies on much shorter timescales than in quasars and occasio... | positron annihilation signatures associated with the outburst of the microquasar v404 cygni |
fundamental differences in the radio properties of red quasars (qsos), as compared to blue qsos, have been recently discovered, positioning them as a potential key population in the evolution of galaxies and black holes across cosmic time. to elucidate the nature of these objects, we exploited a rich compilation of bro... | the multiwavelength properties of red qsos: evidence for dusty winds as the origin of qso reddening |
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