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The ngEHT’s Role in Measuring Supermassive Black Hole Spins [PDF]

open access: yesGalaxies, 2022
While supermassive black-hole masses have been cataloged across cosmic time, only a few dozen of them have robust spin measurements. By extending and improving the existing Event Horizon Telescope (EHT) array, the next-generation Event Horizon Telescope (
Angelo Ricarte   +4 more
doaj   +2 more sources

The NANOGrav 12.5 yr Data Set: Bayesian Limits on Gravitational Waves from Individual Supermassive Black Hole Binaries [PDF]

open access: yesThe Astrophysical Journal Letters, 2023
Pulsar timing array collaborations, such as the North American Nanohertz Observatory for Gravitational Waves (NANOGrav), are seeking to detect nanohertz gravitational waves emitted by supermassive black hole binaries formed in the aftermath of galaxy ...
Zaven Arzoumanian   +78 more
doaj   +2 more sources

Leptonic and Hadronic Radiative Processes in Supermassive-Black-Hole Jets [PDF]

open access: yesGalaxies, 2020
Supermassive black holes lying in the center of galaxies can launch relativistic jets of plasma along their polar axis. The physics of black-hole jets is a very active research topic in astrophysics, owing to the fact that many questions remain open on ...
Matteo Cerruti
doaj   +2 more sources

Formation of Supermassive Black Hole Seeds [PDF]

open access: yesPublications of the Astronomical Society of Australia, 2016
The detection of quasars at z > 6 unveils the presence of supermassive black holes of a few billion solar masses. The rapid formation process of these extreme objects remains a fascinating and open issue. Such discovery implies that seed black holes must
M. Latif, A. Ferrara
semanticscholar   +4 more sources

A dormant overmassive black hole in the early Universe. [PDF]

open access: yesNature
Recent observations have found a large number of supermassive black holes already in place in the first few hundred million years after the Big Bang, many of which seem to be overmassive relative to their host galaxy stellar mass when compared with local
Juodžbalis I   +27 more
europepmc   +2 more sources

The NANOGrav 15 yr Data Set: Constraints on Supermassive Black Hole Binaries from the Gravitational-wave Background [PDF]

open access: yesAstrophysical Journal Letters, 2023
The NANOGrav 15 yr data set shows evidence for the presence of a low-frequency gravitational-wave background (GWB). While many physical processes can source such low-frequency gravitational waves, here we analyze the signal as coming from a population of
G. Agazie   +113 more
semanticscholar   +1 more source

A CEERS Discovery of an Accreting Supermassive Black Hole 570 Myr after the Big Bang: Identifying a Progenitor of Massive z > 6 Quasars [PDF]

open access: yesAstrophysical Journal Letters, 2023
We report the discovery of an accreting supermassive black hole at z = 8.679. This galaxy, denoted here as CEERS_1019, was previously discovered as a Lyα-break galaxy by Hubble with a Lyα redshift from Keck.
R. Larson   +50 more
semanticscholar   +1 more source

First Sagittarius A* Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole in the Center of the Milky Way [PDF]

open access: yes, 2023
We present the first Event Horizon Telescope (EHT) observations of Sagittarius A* (Sgr A$^*$), the Galactic center source associated with a supermassive black hole.
K. Akiyama   +387 more
semanticscholar   +1 more source

The NANOGrav 15 yr Data Set: Bayesian Limits on Gravitational Waves from Individual Supermassive Black Hole Binaries [PDF]

open access: yesAstrophysical Journal Letters, 2023
Evidence for a low-frequency stochastic gravitational-wave background has recently been reported based on analyses of pulsar timing array data. The most likely source of such a background is a population of supermassive black hole binaries, the loudest ...
G. Agazie   +98 more
semanticscholar   +1 more source

Implications for the supermassive black hole binaries from the NANOGrav 15-year data set [PDF]

open access: yesScience China Physics Mechanics and Astronomy, 2023
Several pulsar timing array (PTA) collaborations, including NANOGrav, EPTA, PPTA, and CPTA, have announced the evidence for a stochastic signal consistent with a stochastic gravitational wave background (SGWB).
Yanfeng Bi   +3 more
semanticscholar   +1 more source

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