Insights from JWST observations suggest that AGN feedback evolved from a short-lived, high redshift phase in which radiatively cooled turbulence and/or momentum-conserving outflows stimulated vigorous early star formation (``positive'' feedback), to late, energy-conserving outflows that depleted halo gas reservoirs and quenched star formation. The transition between these two regimes occurred at $z\sim 6$, independently of galaxy mass, for simple assumptions about the outflows and star formation process. Observational predictions provide circumstantial evidence for the prevalence of massive black holes at the highest redshifts hitherto observed, and we discuss their origins.
JWST spectra are consistent with the edge-on star-forming galaxy scenario for the "runaway supermassive black hole"
Instituto de Astrofísica de Canarias(加那利群岛天体物理研究所);Universidad de La Laguna(拉古纳大学);Universidad Nacional Autónoma de México(墨西哥国立自治大学);Institute of Space Sciences (ICE, CSIC)(空间科学研究所)
The Supermassive Black Hole in the Nearby Spiral Galaxy M81: A Robust Mass from JWST/NIRSpec Stellar Dynamics
University of Michigan(密歇根大学);Vietnam National University – Ho Chi Minh City(越南国立大学胡志明市);University of Oxford(牛津大学);International University, Vietnam National University in Ho Chi Minh City(越南国立大学胡志明市国际大学)
Direct-collapse black holes (DCBHs) may be the seeds of the first quasars, over 200 of which have now been detected at $z > 6$ . The James Webb Space Telescope (JWST) could detect DCBHs in the near infrared (NIR) at $z \lesssim 20$ and probe the evolution of primordial quasars at their earliest stages, but only in narrow fields that may not capture many of them. Wide-field NIR surveys by Euclid and the Nancy Grace Roman Survey Telescope (RST) would enclose far greater numbers of DCBHs but only directly detect them at $z \lesssim 6 - 8$ because of their lower sensitivities. However, their large…
The James Webb Space Telescope (JWST) will have the sensitivity to detect early low-mass black holes as they transition from "seeds" to supermassive black holes (BHs). Based on the JAGUAR mock catalog of galaxies, we present a clean color selection that takes advantage of the unique UV slope of accreting supermassive black holes with relatively low mass and high accretion rates. We show for a range of host stellar masses that those galaxies hosting $\sim 10^{6} M_{\odot}$ BHs radiating at >10% of their Eddington luminosity separate in color space from inactive systems. Here we propose a set of…
Gravitational lensing is an important prediction of general relativity, providing both its test and a tool to detect faint but amplified sources and to measure masses of lenses. For some applications (e.g. testing the theory), a point source lensed by a point-like lens would be more advantageous. However, until now only one gravitationally lensed star has been resolved. The future telescopes will resolve very small lensing signatures for stars orbiting the supermassive black hole (SMBH) in the center of the Milky Way. The lensing signatures should however be easier to detect for background sta…
The JWST Ultramassive Galaxy Sample -- II. Supermassive Black Hole Masses for 8 Extreme Early-Type Galaxies via Jeans Anisotropic Modelling of High-Resolution Integral-Field NIRSpec Stellar Kinematics
University of Oxford(牛津大学);University of Michigan(密歇根大学);Space Telescope Science Institute(太空望远镜科学研究所)
本研究利用 JAM 建模 JWST 高分辨率 NIRSpec 恒星运动学,测量 8 个超大质量星系的中心黑洞质量,发现其增长具有高度随机性,并填补了极端质量标度关系的空白。
Tidal disruption event rates across cosmic time: forecasts for LSST, Roman, and JWST and their constraints on the supermassive black hole mass function
Johns Hopkins University(约翰斯·霍普金斯大学);University of Maryland, College Park(马里兰大学帕克分校)
JWST Confirmation of a Runaway Supermassive Black Hole via its Supersonic Bow Shock
Yale University(耶鲁大学);Dragonfly Focused Research Organization(龙卷风重点研究机构);Harvard-Smithsonian Center for Astrophysics(哈佛-史密森尼天体物理中心);University of California, Santa Barbara(加州大学圣塔芭芭拉分校);University of Toronto(多伦多大学);Tel Aviv University(特拉维夫大学);San José State University(圣何塞州立大学);University of California Santa Cruz(加州大学圣克鲁兹分校)
JWST Reveals a Candidate Supermassive Black Hole Binary at z=4.3 in the Brightest Sub-millimeter Galaxy in COSMOS-Web
The University of Texas at Austin(德克萨斯大学奥斯汀分校);University of California Santa Barbara(加州大学圣塔芭芭拉分校);University of Colorado, Boulder(科罗拉多大学博尔德分校);NASA-Goddard Space Flight Center(美国宇航局戈达德太空飞行中心)
Supermassive Black Hole Assembly from Heavy Seeds with Dynamical Friction in the BRAHMA Simulations: Implications for JWST, LISA, and the Local Universe
University of Virginia(弗吉尼亚大学);Virginia Institute for Theoretical Astronomy, University of Virginia(弗吉尼亚大学理论天体物理研究所);University of California Berkeley(加州大学伯克利分校);Center for Computational Astrophysics, Flatiron institute(西蒙斯基金会平顿计算天体物理中心);Leibniz Institute for Astrophysics Potsdam (AIP)(波茨坦阿基米德天体物理研究所);Yale University(耶鲁大学);Black Hole Initiative, Harvard University(哈佛大学黑洞倡议计划)
Galaxies grow their supermassive black holes in concert with their stars, although the relationship between these major galactic components is poorly understood. Observations of the cosmic growth of stars and black holes in galaxies suffer from disjoint samples and the strong effects of dust attenuation. The thermal infrared holds incredible potential for simultaneously measuring both the star formation and black hole accretion rates in large samples of galaxies covering a wide range of physical conditions. Spitzer demonstrated this potential at low redshift, and by observing some of the most …
Supermassive primordial stars in hot, atomically-cooling haloes at $z \sim$ 15 - 20 may have given birth to the first quasars in the universe. Most simulations of these rapidly accreting stars suggest that they are red, cool hypergiants, but more recent models indicate that some may have been bluer and hotter, with surface temperatures of 20,000 - 40,000 K. These stars have spectral features that are quite distinct from those of cooler stars and may have different detection limits in the near infrared (NIR) today. Here, we present spectra and AB magnitudes for hot, blue supermassive primordial…
Supermassive stars with embedded stellar black hole cores: dense assembling star clusters as faint multiple Little Red Dot systems
University of Cambridge(剑桥大学);Kavli Institute for Cosmology, Cambridge (KICC), University of Cambridge(剑桥大学卡弗里宇宙学研究所);Max-Planck-Institut für Astrophysik(马克斯·普朗克天体物理研究所)
Although supermassive black holes (SMBHs) are found at the centers of most galaxies today, over 300 have now been discovered at $z >$ 6, including UHZ1 at $z = 10.1$ and GHZ9 at $z =$ 10.4. They are thought to form when 10$^4$ - 10$^5$ M$_{\odot}$ primordial stars die as direct-collapse black holes (DCBHs) at $z \sim$ 20 - 25. While studies have shown that DCBHs should be visible at birth at $z \gtrsim$ 20 in the near infrared (NIR) to the James Webb Space Telescope (JWST), none have considered SMBH detections at later stages growth down to $z \sim$ 6 - 7. Here, we present continuum NIR lumino…
Little red dots as young supermassive black holes in dense ionized cocoons
University of Manchester(曼彻斯特大学);Cosmic Dawn Center (DAWN)(宇宙黎明中心);Niels Bohr Institute, University of Copenhagen(哥本哈根大学尼尔斯玻尔研究所);Department of Astronomy, University of Geneva(日内瓦大学天文学系);The Queen’s University of Belfast(贝尔法斯特女王大学);University of Sussex(萨塞克斯大学)
The emergence of the first black holes during the first billion years of cosmic history marks a key event in cosmology. Their formation is part of the overall process of ending the cosmic dark ages, when the first stars appeared in low-mass dark matter haloes about a few 100 million years after the Big Bang. The first stars, galaxies, and black holes transformed the Universe from its simple initial state into one of ever increasing complexity. We review recent progress on our emerging theoretical picture of how the first black holes appeared on the cosmic scene, and how they impacted the subse…
The collapse of supermassive primordial stars in hot, atomically-cooled halos may have given birth to the first quasars at $z \sim$ 15 - 20. Recent numerical simulations of these rapidly accreting stars reveal that they are cool, red hypergiants shrouded by dense envelopes of pristine atomically-cooled gas at 6,000 - 8,000 K, with luminosities $L$ $\gtrsim$ 10$^{10}$ L$_{\odot}$. Could such luminous but cool objects be detected as the first stage of quasar formation in future near infrared (NIR) surveys? We have now calculated the spectra of supermassive primordial stars in their birth envelop…
We measure the extinction law in the 30 Dor star formation region in the Large Magellanic Cloud using Early Release Observations taken with Near-Infrared Camera (NIRCam) onboard the JWST, thereby extending previous studies with the Hubble Space Telescope to the infrared. We use red clump stars to derive the direction of the reddening vector in twelve bands and present the extinction law in this massive star forming region from $0.3$ to $4.7\,μ$m. At wavelengths longer than 1 $μ$m, we find a ratio of total and selective extinction twice as high as in the diffuse Milky Way interstellar medium an…
Globular clusters contain multiple stellar populations with peculiar chemical compositions. Pollution of the intracluster gas by an early population of fast-evolving stars is the most common scenario for explaining the observations. Stars with masses in excess of 1000 Msun have recently been suggested as potential polluters. We investigate the spectral properties of proto-GCs that would host a supermassive star. Our main goal is to quantify how such a star would affect the integrated light of the cluster, and to study the detectability of such objects. We computed non-LTE atmosphere models for…
It is now clear that a significant population of accreting black holes are undetected by commonly employed optical, mid-infrared color, X-ray, and radio selection methods due to obscuration or contamination of the emission from the nuclear region caused by star formation in the host galaxy. These elusive active galactic nuclei (AGNs) are an important component of the AGN population. They are often found in mergers, where significant black hole growth likely takes place, and in the lowest mass galaxies or galaxies that lack classical bulges, a demographic that places important constraints on mo…
Imaging with the James Webb Space Telescope (JWST) will allow for observing the bulk of distant galaxies at the epoch of reionisation. The recovery of their properties, such as age, color excess E(B-V), specific star formation rate (sSFR) and stellar mass, will mostly rely on spectral energy distribution fitting, based on the data provided by JWST's two imager cameras, namely the Near Infrared Camera (NIRCam) and the Mid Infrared Imager (MIRI). In this work we analyze the effect of choosing different combinations of NIRCam and MIRI broad-band filters, from 0.6 μm to 7.7 μm, on the recovery of …
Early Supermassive Black Holes and Little Red Dots Require Free-Fall Growth
Department of Astronomy, University of Texas, Austin(德克萨斯大学奥斯汀分校天文学系);Cosmic Frontier Center, The University of Texas, Austin(德克萨斯大学奥斯汀分校宇宙前沿中心);Weinberg Institute for Theoretical Physics, University of Texas, Austin(德克萨斯大学奥斯汀分校温伯格理论物理研究所)
We present criteria for separately classifying stars and unresolved background galaxies in photometric catalogs generated with the point spread function (PSF) fitting photometry software DOLPHOT from images taken of Draco II, WLM, and M92 with the Near Infrared Camera (NIRCam) on JWST. Photometric quality metrics from DOLPHOT in one or two filters can recover a pure sample of stars. Conversely, colors formed between short-wavelength (SW) and long-wavelength (LW) filters can be used to effectively identify pure samples of galaxies. Our results highlight that the existing DOLPHOT output paramete…