AGN on the move: A search for off-nuclear AGN from recoiling SMBHs and ongoing galaxy mergers with the Zwicky Transient Facility
Charlotte Ward, Suvi Gezari, Sara Frederick, Erica Hammerstein, Peter Nugent, Sjoert van Velzen, Andrew Drake, Abigail García-Pérez, Immaculate Oyoo, Eric C. Be… 展开作者
Charlotte Ward, Suvi Gezari, Sara Frederick, Erica Hammerstein, Peter Nugent, Sjoert van Velzen, Andrew Drake, Abigail García-Pérez, Immaculate Oyoo, Eric C. Bellm, Dmitry A. Duev, Matthew J. Graham, Mansi M. Kasliwal, Stephen Kaye, Ashish A. Mahabal, Frank J. Masci, Ben Rusholme, Maayane T. Soumagnac, Lin Yan
A supermassive black hole (SMBH) ejected from the potential well of its host galaxy via gravitational wave recoil carries important information about the mass ratio and spin alignment of the pre-merger SMBH binary. Such a recoiling SMBH may be detectable as an active galactic nucleus (AGN) broad line region offset by up to 10\,kpc from a disturbed host galaxy. We describe a novel methodology using forward modeling with \texttt{The Tractor} to search for such offset AGN in a sample of 5493 optically variable AGN detected with the Zwicky Transient Facility (ZTF). We present the discovery of 9 AGN which may be spatially offset from their host galaxies and are candidates for recoiling SMBHs. Five of these offset AGN exhibit double-peaked broad Balmer lines which may arise from unobscured accretion disk emission and four show radio emission indicative of a relativistic jet. The fraction of double-peaked emitters in our spatially offset AGN sample is significantly larger than the 16\% double-peaked emitter fraction observed for ZTF AGN overall. In our sample of variable AGN we also identified 52 merging galaxies, including a new spectroscopically confirmed dual AGN. Finally, we detected the dramatic rebrightening of SDSS1133, a previously discovered variable object and recoiling SMBH candidate, in ZTF. The flare was accompanied by the re-emergence of strong P-Cygni line features indicating that it may be an outbursting luminous blue variable star.
Supermassive black hole binaries (SMBHBs) are the products of frequent galaxy mergers. The coalescence of the SMBHBs is a distinct source of gravitational wave (GW) radiation. The detections of the strong GW radiation and their possible electromagnetic counterparts are essential. Numerical relativity suggests that the post-merger supermassive black hole (SMBH) gets a kick velocity up to 4000 km/s due to the anisotropic GW radiations. Here we investigate the dynamical co-evolution and interaction of the recoiling SMBHs and their galactic stellar environments with one million direct N-body simul…
We follow trajectories of recoiling supermassive black holes (SMBHs) in analytical and numerical models of galaxy merger remnants with masses of $10^{11} \rm{M_{sun}}$ and $10^{12} \rm{M_{sun}}$. We construct various merger remnant galaxies in order to investigate how the central SMBH mass and the mass ratio of progenitor galaxies influence escape velocities of recoiling SMBHs. Our results show that static analytical models of major merger remnant galaxies overestimate the SMBHs escape velocities. During major mergers violent relaxation leads to the decrease of galaxy mass and lower potential …
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…
In this paper, we present an algorithm to correct optical light curves obtained using The Zwicky Transient Facility Forced Photometry Service and its application to the analysis of optical variability of 136 actvie galactic nuclei (AGN) powered by "light-weight" supermassive black holes (SMBH; $M_{BH}$<2*10^6 $\odot$) including 24 intermediate-mass black holes (IMBH; $M_{BH}$<2*10^5 $\odot$). We detected variability in nearly all sources and also analyzed its dependence on the X-ray luminosity for 101 objects. We also identified a previously unknown candidate tidal disruption event (TDE) in SD…
A recoiling supermassive black hole in a powerful quasar
Space Telescope Science Institute for the European Space Agency (ESA), ESA Office（欧洲空间局（ESA）太空望远镜科学研究所，ESA办公室）；The William H. Miller III Department of Physics & Astronomy, Johns Hopkins University（约翰斯·霍普金斯大学威廉·H·米勒三世物理与天文学系）；IPAC, California Institute of Technology（加州理工学院 IPAC）；Dipartimento di Fisica "G. Occhialini'', Università degli Studi di Milano-Bicocca（米兰比可卡大学 G. Occhialini 物理系）；INFN, Sezione di Milano-Bicocca（意大利国家核物理研究所米兰比可卡分部）；Dipartimento di Matematica e Fisica, Università degli Studi Roma Tre（罗马第三大学数学与物理系）；INAF - Osservatorio Astrofisico di Torino（意大利国家天体物理研究所都灵天文台）；INAF-Osservatorio di Astrofisica e Scienza dello Spazio di Bologna（意大利国家天体物理研究所博洛尼亚天体物理与空间科学观测站）；Institute of Astronomy, Graduate School of Science, the University of Tokyo（东京大学大学院理学研究科天文学系）；Astronomy Data Center, National Astronomical Observatory of Japan（日本国立天文台天文数据中心）；NASA-Goddard Space Flight Center（美国宇航局戈达德太空飞行中心）；Department of Physics, University of Maryland, Baltimore County（马里兰大学巴尔的摩分校物理系）；Advanced Technology Center, National Astronomical Observatory of Japan（日本国立天文台先进技术中心）；Space Telescope Science Institute（太空望远镜科学研究所）；Dept. of Astronomy, University of Maryland, College Park（马里兰大学学院公园分校天文学系）
3C186 is a powerful radio loud quasar (QSO) at the center of a cool-core cluster at z=1.06. Previous studies reported evidence for a projected spatial offset of ~1'' between the isophotal center of the galaxy and the point-source QSO as well as a spectral shift of ~2000 km/s between the narrow and broad line region of the system. In this work we report high-resolution molecular gas CO(4-3) observations of the system taken with NOEMA interferometer. We clearly detect a large reservoir of molecular gas, $M_{H_2}\sim8\times10^{10}~M_\odot$, that is cospatial with the host galaxy and likely associ…
We report the discovery of a kiloparsec-scale triple supermassive black hole system at $z=0.256$: SDSS J1056+5516, discovered by our systematic search for binary quasars. The system contains three strong emission-line nuclei, which are offset by $<250~{\rm km~s^{-1}}$ and by 15-18 kpc in projected separation, suggesting that the nuclei belong to the same physical structure. The system includes a tidal arm feature spanning $\sim100$ kpc in projected distance at the systems' redshift, inhabiting an ongoing or recent galaxy merger. Based on our results, such a structure can only satisfy one of th…
Predicting Potential Host Galaxies of Supermassive Black Hole Binaries Based on Stellar Kinematics in Archival IFU Surveys
Bishop’s University（主教大学）；Trottier Space Institute and Department of Physics, McGill University（麦吉尔大学特鲁蒂尔太空研究所和物理系）；California Institute of Technology（加州理工学院）；Vanderbilt University（范德堡大学）
Recoiling supermassive black holes (SMBHs) are considered one plausible physical mechanism to explain high velocity shifts between narrow and broad emission lines sometimes observed in quasar spectra. If the sphere of influence of the recoiling SMBH is such that only the accretion disc is bound, the dusty torus would be left behind, hence the SED should then present distinctive features (i.e. a mid-infrared deficit). Here we present results from fitting the Spectral Energy Distributions (SEDs) of 32 Type-1 AGN with high velocity shifts between broad and narrow lines. The aim is to find peculia…
H$_2$O megamasers residing in the accretion disks of active galactic nuclei (AGN) exhibit Keplerian rotation about the central supermassive black hole (SMBH). Such disk maser systems are excellent tools for diagnosing the kinematic status of the SMBH, and they currently provide the only direct and unambiguous measure of SMBH velocities outside of the Milky Way. We have measured the galaxy recession velocities for a sample of 10 maser disk systems using a combination of spatially resolved HI disk modeling, spatially integrated HI profile fitting, and optical spectral line and continuum fitting.…
Active galactic nuclei do not exhibit strictly sinusoidal brightness variations
California Institute of Technology（加州理工学院）；Max Planck Institute for Astronomy（马克斯·普朗克天文学研究所）；Center for Computational Astrophysics, Flatiron Institute（平顿研究所计算天体物理中心）；New York University（纽约大学）
Chandra X-ray Observations of Quasars with Velocity-Offset Broad Lines: Assessing the Binary Supermassive Black Hole Hypothesis
Binghamton University（宾汉姆顿大学）；The Pennsylvania State University（宾夕法尼亚州立大学）；Georgia Institute of Technology（佐治亚理工学院）；West Virginia University（西弗吉尼亚大学）；Canadian Institute for Advanced Research（加拿大高级研究院）；Jet Propulsion Laboratory, California Institute of Technology（加州理工学院喷气推进实验室）
We investigate the evolution of intermediate-mass (IMBHs), stellar (BHs) and binary black holes (BHBs), deposited near a supermassive black hole (SMBH) by a population of massive star clusters. Stellar BHs rapidly segregate around the SMBH, driving the formation of extreme mass-ratio inspirals that coalesce at a rate $Γ= 0.02-0.2$ yr$^{-1}$ Gpc$^{-3}$ at redshift $z=0$. A few IMBHs orbiting the SMBH favour the formation of massive pairs that coalescence within a Hubble time, being the merger rate for this channel $Γ=0.03$ yr$^{-1}$ Gpc$^{-3}$. Recoiling kicks post-merger can eject the remnant …
Off-nucleus active galactic nuclei (AGN) can be signposts of inspiraling supermassive black holes (SMBHs) on galactic scales, or accreting SMBHs recoiling after the coalescence of a SMBH binary or slingshot from three-body interactions. Because of the stochastic variability of AGN, the measured photocenter of an unresolved AGN-host system will display astrometric jitter that depends on the off-nucleus distance of the AGN, the total photometric variability of the system, and the AGN-host contrast. Here we use the precision astrometry from Gaia DR2 to constrain the off-nucleus population of a lo…
The ePESSTO+ census of ZTF nuclear transients. I. What flares in galactic nuclei?
Technical University of Denmark（丹麦技术大学）；University of Belgrade（贝尔格莱德大学）；University of Warsaw（华沙大学）；University of Turku（图尔库大学）；Institute of Space Sciences (ICE, CSIC)（空间科学研究所（ICE，CSIC））；Isaac Newton Group of Telescopes（艾萨克·牛顿望远镜组）；Queens University Belfast（贝尔法斯特女王大学）；National Centre for Nuclear Research（国家核研究中心）；University of Southampton（南安普顿大学）；National Central University（中央大学）；Sorbonne University（索邦大学）
