With projects such as Laser Interferometer Space Antenna (LISA) and Pulsar Timing Arrays expected to detect gravitational waves from supermassive black hole mergers in the near future, it is key that we understand what we expect those detections to be, and maximize what we can learn from them. To address this, we study the mergers of supermassive black holes in the Illustris simulation, the overall rate of mergers, and the correlation between merging black holes and their host galaxies. We find that these mergers occur in typical galaxies along the $M_{\rm{BH}}-M_*$ relation, and that between LISA and PTAs we expect to probe the full range of galaxy masses. As galaxy mergers can trigger increased star formation, we find that galaxies hosting low-mass black hole mergers tend to show a slight increase in star formation rates compared to a mass-matched sample. However, high-mass merger hosts have typical star formation rates, due to a combination of low gas fractions and powerful AGN feedback. Although minor black hole mergers do not correlate with disturbed morphologies, major mergers (especially at high-masses) tend to show morphological evidence of recent galaxy mergers which survives for ~500 Myr. This is on the same scale as the infall/hardening time of the merging black holes, suggesting that electromagnetic followups to gravitational wave signals may not be able to observe this correlation. We further find that incorporating a realistic timescale delay for the black hole mergers could shift the distribution of merger masses toward higher-masses, decreasing the rate of LISA detections while increasing the rate of PTA detections.
Supermassive black hole binary systems (SMBHBs) emitting gravitational waves may be traced by periodic light curves. We assembled a catalog of 149 such periodic light curves, and using their masses, distances, and periods, predicted the gravitational-wave strain and detectability of each binary candidate using all-sky detection maps. We found that the International Pulsar Timing Array (IPTA) provides almost uniform sky coverage -- a unique ability of the IPTA -- and by 2025 will improve NANOGrav's current minimum detectable strain by a factor of 6, and its volume by a factor of 216. Moreover, …
Time-domain datasets of many varieties can be prone to statistical outliers that result from instrumental or astrophysical anomalies. These can impair searches for signals within the time series and lead to biased parameter estimation. Versatile outlier mitigation methods tuned toward multimessenger time-domain searches for supermassive binary black holes have yet to be fully explored. In an effort to perform robust outlier isolation with low computational costs, we propose a Gibbs sampling scheme. This provides structural simplicity to outlier modeling and isolation, as it requires minimal mo…
HECATEv2: An all-sky galaxy catalogue for multimessenger astrophysics
University of Crete（克里特大学）；Foundation for Research and Technology-Hellas（希腊研究与技术基金会）；Institute of Space Sciences (ICE, CSIC)（空间科学研究所（ICE, CSIC））；Institut d’Estudis Espacials de Catalunya (IEEC)（加泰罗尼亚太空研究学院（IEEC））；Astronomical Institute, Academy of Sciences（科学院天文研究所）；NASA Goddard Space Flight Center（美国宇航局戈达德太空飞行中心）；Johns Hopkins University（约翰斯·霍普金斯大学）；University of Maryland, Baltimore County（马里兰大学巴尔的摩县分校）
Supermassive black hole (BH) binaries would comprise the strongest sources of gravitational waves (GW) once they reach <<1 pc separations, for both pulsar timing arrays (PTAs) and space based (SB) detectors. While BH binaries coalescences constitute a natural outcome of the cosmological standard model and galaxy mergers, their dynamical evolution is still poorly understood and therefore their abundances at different stages. We use a dynamical model for the decay of BH binaries coupled with a cosmological simulation and semi-empirical approaches to the occupation of haloes by galaxies and BHs, …
We present multi-frequency Very Long Baseline Array (VLBA) follow-up observations of VLBA Imaging and Polarimetry Survey sources identified as likely compact symmetric objects (CSOs) or super-massive binary black holes (SBBHs). We also present new spectroscopic redshifts for 11 sources observed with the Hobby-Eberly Telescope. While no new SBBHs can be confirmed from these observations, we have identified 24 CSOs in the sample, 15 of which are newly designated, and refuted 52 candidates leaving 33 unconfirmed candidates. This is the first large uniform sample of CSOs which can be used to elici…
Supermassive black hole binaries may be detectable by an upcoming suite of gravitational wave experiments. Their binary nature can also be revealed by radio jets via a short-period precession driven by the orbital motion as well as the geodetic precession at typically longer periods. We have investigated Karl G. Jansky Very Large Array (VLA) and MERLIN radio maps of powerful jet sources for morphological evidence of geodetic precession. For perhaps the best studied source, Cygnus A, we find strong evidence for geodetic precession. Projection effects can enhance precession features, for which w…
We present new and stronger evidence for a previously reported relationship between galactic spiral arm pitch angle P (a measure of the tightness of spiral structure) and the mass M_BH of a disk galaxy's nuclear supermassive black hole (SMBH). We use an improved method to accurately measure the spiral arm pitch angle in disk galaxies to generate quantitative data on this morphological feature for 34 galaxies with directly measured black hole masses. We find a relation of log(M/M_sun) = (8.21 +/- 0.16) - (0.062 +/- 0.009)P. This method is compared with other means of estimating black hole mass …
We use a semianalytic model of galaxy formation to compare the predictions of two quenching scenarios: halo quenching and black-hole (BH) quenching. After calibrating both models so that they fit the mass function of galaxies, BH quenching is in better agreement with the fraction of passive galaxies as a function of stellar mass $M_*$ and with the galaxy morphological distribution on a star-formation-rate vs. $M_*$ diagram. Besides this main finding, there are two other results from this research. First, a successful BH-quenching model requires that minor mergers contribute to the growth of su…
We have carried out a systematic search for recoiling supermassive black holes (rSMBH) using the Chandra Source and SDSS Cross Matched Catalog. From the survey, we have detected a potential rSMBH, 'CXO J101527.2+625911' at z=0.3504. The CXO J101527.2+625911 has a spatially offset (1.26$\pm$0.05 kpc) active SMBH and kinematically offset broad emission lines (175$\pm$25 km s$^{\rm -1}$ relative to systemic velocity). The observed spatial and velocity offsets suggest this galaxy could be a rSMBH, but we also have considered a possibility of dual SMBH scenario. The column density towards the galax…
Sgr A* as a Galactic PeVatron: Multimessenger Signatures of the Magnetic Penrose Process
Universidad Politécnica de Madrid（马德里理工大学）；Instituto de Física Teórica UAM-CSIC（UAM-CSIC理论物理研究所）；Universidad Autónoma de Madrid（马德里自治大学）；Escuela Politécnica Superior, Universidad San Pablo-CEU（圣保罗ceu大学高等理工学院）；Utah State University（犹他州立大学）
The Next-Generation Very Large Array (ngVLA) has the potential to be a workhorse for the discovery and study of paired supermassive black holes either at large separations (dual) or in tightly bound systems (binary). In this chapter, we outline the science case for the study of these supermassive pairs, and summarize discovery methods that can be used at radio wavelengths to discover them: including morphological, spectral, and time-domain identifications. One critical aspect of this work is that multi-messenger binary black hole studies may be possible with the ngVLA when combined with gravit…
The multimessenger view of Pulsar Timing Array black holes with the Horizon-AGN simulation
Université Paris Cité, CNRS, Astroparticule et Cosmologie（巴黎西岱大学）；Institut d’Astrophysique de Paris, UMR 7095, CNRS and Sorbonne Université（巴黎天体物理学研究所）；Institute for Astronomy, University of Edinburgh（爱丁堡大学天文研究所）；IRAP, Université de Toulouse, CNRS, UPS, CNES（图卢兹大学）
As part of the mm-Wave Interferometric Survey of Dark Object Masses (WISDOM) project, we present an estimate of the mass of the supermassive black hole (SMBH) in the nearby fast-rotating early-type galaxy NGC4697. This estimate is based on Atacama Large Millimeter/submillimeter Array (ALMA) cycle-3 observations of the 12CO(2-1) emission line with a linear resolution of 29 pc (0.53"). We find that NGC4697 hosts a small relaxed central molecular gas disc with a mass of 1.6x10^7 Msun, co-spatial with the obscuring dust disc visible in optical Hubble Space Telescope (HST) imaging. We also resolve …
Stars that plunge into the center of a galaxy are tidally perturbed by a supermassive black hole (SMBH), with closer encounters resulting in larger perturbations. Exciting these tides comes at the expense of the star's orbital energy, which leads to the naive conclusion that a smaller pericenter (i.e., a closer encounter between the star and SMBH) always yields a more tightly bound star to the SMBH. However, once the pericenter distance is small enough that the star is partially disrupted, morphological asymmetries in the mass lost by the star can yield an \emph{increase} in the orbital energy…
A population of LIGO-Virgo-KAGRA mergers happening inside active galactic nuclei
Beijing Institute of Mathematical Sciences and Applications（北京数学与应用科学研究所）；Department of Physics, National Institute of Technology Agartala（阿加塔拉国家理工学院物理系）；Institute for Gravitation and the Cosmos, Department of Physics, Pennsylvania State University（宾夕法尼亚州立大学引力与宇宙学研究所）；National Institute of Technology Agartala（阿加塔拉国家理工学院）
We study the relations between the mass of the central black hole (BH) $M_{\rm BH}$, the dark matter halo mass $M_{\rm h}$, and the stellar-to-halo mass fraction $f_\star\propto M_\star/M_{\rm h}$ in a sample of $55$ nearby galaxies with dynamically measured $M_{\rm BH}>10^6\,{\rm M}_\odot$ and $M_{\rm h}>5\times10^{11}\,{\rm M}_\odot$. The main improvement with respect to previous studies is that we consider both early- and late-type systems for which $M_{\rm h}$ is determined either from globular cluster dynamics or from spatially resolved rotation curves. Independently of their structural p…
COSMOS-Web: A Multi-wavelength Morphological Catalog of ~780,000 Galaxies
Rochester Institute of Technology（罗切斯特理工学院）；Hunan Normal University（湖南师范大学）；University of Hawaii, Hilo（夏威夷大学希洛分校）；Caltech/IPAC（加州理工学院/IPAC）；Université Paris-Saclay（巴黎萨克雷大学）；Université Paris Cité（巴黎西岱大学）；Space Telescope Science Institute（太空望远镜科学研究所）；Aix Marseille Univ（艾克斯-马赛大学）；The University of Texas at Austin（德克萨斯大学奥斯汀分校）；University of California, Santa Barbara（加利福尼亚大学圣塔芭芭拉分校）；Cosmic Dawn Center (DAWN)（宇宙黎明中心）
We show that the relation between the mass of supermassive black holes located in the center of the host galaxies and the kinetic energy of random motions of the corresponding bulges is a useful tool to study the evolution of galaxies. In the form log[M_BH] = b + m log[M_G sigma^2/c^2], the best-fitting results for a sample of 64 galaxies of various morphological types are the slope m=0.80 and the normalization b=4.53. We note that, in analogy with the H-R diagram for stars, each morphological type of galaxy generally occupies a different area in the M_BH - (M_G sigma^2)/c^2 plane. In particul…
Motivated by advances in observational searches for sub-parsec supermassive black hole binaries (SBHBs) made in the past few years we develop a semi-analytic model to describe spectral emission line signatures of these systems. The goal of this study is to aid the interpretation of spectroscopic searches for binaries and help test one of the leading models of binary accretion flows in the literature: SBHB in a circumbinary disk. In this work we present the methodology and a comparison of the preliminary model with the data. We model SBHB accretion flows as a set of three accretion disks: two m…
The TNG50 cosmological simulation produces X-ray emitting bubbles, shells, and cavities in the circumgalactic gas above and below the stellar disks of Milky Way- and Andromeda-like galaxies with morphological features reminiscent of the eROSITA and Fermi bubbles in the Galaxy. Two-thirds of the 198 MW/M31 analogues inspected in TNG50 at z=0 show one or more large-scale, coherent features of over-pressurized gas that impinge into the gaseous halo. Some of the galaxies include a succession of bubbles or shells of increasing size, ranging from a few to many tens of kpc. These are prominent in gas…
Direct pathway to the Early Supermassive Black Holes: A Red Super-Eddington Quasar in a Massive Starburst Host at $z=7.2$
University of Toronto（多伦多大学）；Dunlap Institute for Astronomy and Astrophysics（邓普天文学与天体物理学研究所）；Cosmic Dawn Center (DAWN)（宇宙黎明中心）；Niels Bohr Institute（尼尔斯·玻尔研究所）；University of Copenhagen（哥本哈根大学）；Max-Planck-Institut für extraterrestrische Physik（马克斯·普朗克地外物理研究所）；Kavli Institute for Astronomy and Astrophysics（开普勒天文与天体物理研究所）；Peking University（北京大学）；Department of Astronomy, School of Physics, Peking University（北京大学物理学院天文学系）；University of Texas, Austin（德克萨斯大学奥斯汀分校）；Weinberg Institute for Theoretical Physics（温伯格理论物理研究所）；Cosmic Frontier Center（宇宙前沿中心）；Centro de Astrobiología (CAB)（天体生物学中心）；CSIC-INTA（西班牙国家研究委员会-国家航空航天技术研究所）
Forged in Quenching: Morphological Transformation across Star-forming and Quiescent Galaxies in EAGLE
Institute for Computational Cosmology, Department of Physics, Durham University（达勒姆大学物理学院宇宙计算研究所）；Centre for Extragalactic Astronomy, Department of Physics, Durham University（达勒姆大学物理学院河外天文学中心）；Institute for Data Science, Durham University（达勒姆大学数据科学研究所）；Center for Astronomy and Astrophysics and Department of Physics, Fudan University（复旦大学物理学院天文与天体物理中心）
Unveiling the properties of galaxy cores excavated by supermassive black hole binaries with SHARP
INAF – Osservatorio Astronomico di Padova（意大利国家天体物理研究所帕多瓦天文台）；INAF – Osservatorio Astronomico d’Abruzzo（意大利国家天体物理研究所阿布鲁佐天文台）；Dipartimento di Fisica e Astronomia “G. Galilei”, Università di Padova（帕多瓦大学伽利略物理与天文系）；INAF - Osservatorio Astronomico di Brera（意大利国家天体物理研究所布雷拉天文台）；School of Mathematics and Physics, University of Surrey（萨里大学数理学院）
We investigate the possible link between mergers and the enhanced activity of supermassive black holes (SMBHs) at the centre of galaxies, by comparing the merger fraction of a local sample (0.003 =< z < 0.03) of active galaxies - 59 active galactic nuclei (AGN) host galaxies selected from the all-sky Swift BAT (Burst Alert Telescope) survey - with an appropriate control sample (247 sources extracted from the Hyperleda catalogue) that has the same redshift distribution as the BAT sample. We detect the interacting systems in the two samples on the basis of non-parametric structural indexes of co…
It is believed that the gas accretion onto the supermassive black holes (SMBHs) is the main process of powering its luminous emission, which occurs in optical, UV and X-ray regimes and less frequently in radio waves. The observational fact that only a few percent of quasars are radio-loud is still an unresolved issue concerning the understanding of the active galactic nucleus (AGN) population. Here we present a detection of a rapid transition from the radio-quiet to the radio-loud mode in quasar 013815+00 (z=0.94) which coincides with changes of its UV-optical continuum and the low ionization …
We present a combined morphological and X-ray analysis of Was 49, an isolated, dual AGN system notable for the presence of a dominant AGN Was 49b in the disk of the primary galaxy Was 49a, at a projected radial distance of 8 kpc from the nucleus. Using X-ray data from Chandra, NuSTAR, and Swift, we find that this AGN has a bolometric luminosity of L_bol ~ 2 x 10^45 erg/s, with a black hole mass of M_BH=1.3^{+2.9}_{-0.9} x 10^8 M_Sol. Despite its large mass, our analysis of optical data from the Discovery Channel Telescope shows that the supermassive black hole is hosted by a stellar counterpar…
Galaxy mergers are capable of triggering both star formation and active galactic nuclei (AGN) and therefore may represent an important pathway in the co-evolution of galaxies and supermassive black holes (SMBHs). However, correlated enhancements of merger-induced star formation and AGN triggering may be hidden by the variable conditions and timescales during which they occur. In Paper I, we presented evidence of merger-triggered AGN in a sample of six late-stage galaxy mergers (2-8 kpc nuclear separations). In this follow-up work, we use multi-wavelength Hubble Space Telescope imaging and addi…
We investigate the location of an ultra-hard X-ray selected sample of AGN from the Swift Burst Alert Telescope (BAT) catalog with respect to the main sequence (MS) of star-forming galaxies using Herschel-based measurements of the star formation rate (SFR) and stellar mass (\mstar) from Sloan Digital Sky Survey (SDSS) photometry where the AGN contribution has been carefully removed. We construct the MS with galaxies from the Herschel Reference Survey and Herschel Stripe 82 Survey using the exact same methods to measure the SFR and \mstar{} as the Swift/BAT AGN. We find a large fraction of the S…
QPEs from Warped Disk Collisions with EMRIs: Brightness-Recurrence Diagram and Gravitational-Wave Follow-up
Wuhan University（武汉大学）；Centro de Astrobiología (CAB), CSIC-INTA（天体生物学中心（CAB），西班牙国家航空航天技术研究委员会-国家航空技术研究所）；University of Science and Technology of China（中国科学技术大学）；Tsung-Dao Lee Institute, Shanghai Jiao-Tong University（上海交大李政道研究所）；Shanghai Jiao-Tong University（上海交通大学）
We derive the dependence of the fraction of passive central galaxies on the mass of their supermassive black holes for a sample of over 400,000 SDSS galaxies at z < 0.2. Our large sample contains galaxies in a wide range of environments, with stellar masses 8 < log(M*/Msun) < 12, spanning the entire morphological spectrum from pure disks to spheroids. We derive estimates for the black hole masses from measured central velocity dispersions and bulge masses, using a variety of published empirical relationships. We find a very strong dependence of the passive fraction on black hole mass, which is…
In this second paper of a series of papers based on the FIRST and SDSS surveys we investigate the evolution of galaxy morphology and nuclear activity in the look-back time of the SDSS (~2 Gyrs) for a sample of ~150000 galaxies in the local universe. We demonstrate an evolution in the strength of the radio power and the spectroscopic emission-lines typical of AGN, as well as in the morphology of their hosts. Such evolution appears more substantial for less luminous systems, and is possibly the low-redshift tail of the downsizing in star-formation, AGN activity and supermassive black hole build-…
We explore the galaxy structure of four tidal disruption event (TDE) host galaxies on 30 pc to kpc scales using HST WFC3 multi-band imaging. The star formation histories of these hosts are diverse, including one post-starburst galaxy (ASASSN-14li), two hosts with recent weak starbursts (ASASSN-14ae and iPTF15af), and one early type (PTF09ge). Compared to early type galaxies of similar stellar masses, the TDE hosts have higher central surface brightnesses and stellar mass surface densities on 30-100 pc scales. The TDE hosts do not show the large, kpc-scale tidal disruptions seen in some post-st…
Binary active galactic nuclei (AGNs) provide clues to how gas-rich mergers trigger and fuel AGNs and how supermassive black hole (SMBH) pairs evolve in a gas-rich environment. While significant effort has been invested in their identification, the detailed properties of binary AGNs and their host galaxies are still poorly constrained. In a companion paper, we examined the nature of ionizing sources in the double nuclei of four kpc-scale binary AGNs with redshifts between 0.1~0.2. Here, we present their host galaxy morphology based on F336W (U-band) and F105W (Y-band) images taken by the Wide F…
We use the TNG100 simulation of the IllustrisTNG project to investigate the stellar specific angular momenta ($j_{\ast}$) of $\sim$12,000 central galaxies at $z=0$ in a full cosmological context, with stellar masses ($M_{\ast}$) ranging from $10^{9}$ to $10^{12} \, {\rm M}_{\odot}$. We find that the $j_{\ast}$-$M_{\ast}$ relations for early-type and late-type galaxies in IllustrisTNG are in good overall agreement with observations, and that these galaxy types typically `retain' $\sim$10-20 and $\sim$50-60 per cent of their host haloes' specific angular momenta, respectively, with some dependen…
[Abridged] Tight correlations between supermassive black hole (SMBH) mass ($M_{\rm BH}$) and the properties of the host galaxy have useful implications for our understanding of the growth of SMBHs and evolution of galaxies. Here, we present newly observed correlations between $M_{\rm BH}$ and the host galaxy total UV$-$ [3.6] color ($\mathcal{C_{\rm UV,tot}}$, Pearson's r = $0.6-0.7$) for a sample of 67 galaxies (20 early-type galaxies and 47 late-type galaxies) with directly measured $M_{\rm BH}$ in the GALEX/S$^{4}$G survey. The colors are carefully measured in a homogeneous manner using the…
We have assembled the largest sample of ultra hard X-ray selected (14-195 keV) AGN with host galaxy optical data to date, with 185 nearby (z<0.05), moderate luminosity AGN from the Swift BAT sample. The BAT AGN host galaxies have intermediate optical colors (u-r and g-r) that are bluer than a comparison sample of inactive galaxies and optically selected AGN from the Sloan Digital Sky Survey (SDSS) which are chosen to have the same stellar mass. Based on morphological classifications from the RC3 and the Galaxy Zoo, the bluer colors of BAT AGN are mainly due to a higher fraction of mergers and …
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
