Results 1 to 10 of about 132,127 (279)
The ngEHT’s Role in Measuring Supermassive Black Hole Spins [PDF]
Galaxies, 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
Investigation of some galactic and extragalactic gravitational phenomena [PDF]
Serbian Astronomical Journal, 2012 Here we present a short overview of the most important results of our investigations of the following galactic and extragalactic gravitational phenomena: supermassive black holes in centers of galaxies and quasars, supermassive black hole ...
Jovanović P.
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An Upper Limit on the Charge of the Black Hole Sgr A* from EHT Observations
The Astrophysical Journal, 2023 The Event Horizon Telescope (EHT) recently released an image of the supermassive black hole Sgr A* showing an angular shadow diameter d _sh = 48.7 ± 7 μ as and Schwarzschild shadow deviation $\delta =-{0.08}_{-0.09}^{+0.09}\,(\mathrm{VLTI})$ , $-{0.04}_{-
Sushant G. Ghosh, Misba Afrin
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Decomposition of the central structure of NGC 2273 in the NIR: A case study
Astronomische Nachrichten, Volume 344, Issue 10, December 2023., 2023 Abstract The Seyfert 2 galaxy NGC 2273 is a prime target to explore how active nuclei can be fed. It has a star‐forming innermost nuclear ring with a radius of 0.33kpc from where material may be funneled to the supermassive black hole in its center. In this article, we discuss high‐resolution adaptive optics aided JHKs images of NGC 2273 taken with the
L. Schey +13 more
wiley +1 more source
On the Formation and Interaction of Multiple Supermassive Stars in Cosmological Flows
The Astrophysical Journal, 2023 Supermassive primordial stars with masses exceeding ∼10 ^5 M _⊙ that form in atomically cooled halos are the leading candidates for the origin of high-redshift quasars at z > 6.
Tyrone E. Woods +3 more
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Astronomische Nachrichten, Volume 344, Issue 8-9, October-November 2023., 2023 The Potsdam Arrayed Waveguide Spectrograph (PAWS) is based on an integrated photonic spectrograph designed and developed by innoFSPEC to work in the astronomical H‐band. PAWS demonstrates how a traditional bulk optics spectrograph can be miniaturized and additionally serves as a tool for testing in‐house developed astrophotonical devices.
Eloy Hernandez +6 more
wiley +1 more source
PAWS and POCO: NIR Astrophotonic Instruments for Astronomy
Astronomische Nachrichten, Volume 344, Issue 8-9, October-November 2023., 2023 Abstract For near‐infrared ground and space‐based astronomy, compact photonic devices can replace the large bulk optical components in spectrographs, frequency combs, beam combiners, and sky subtraction filters, thus saving cost, reducing volume, weight, and power requirements.
Kalaga Madhav +8 more
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Characterization of a C‐RED One camera for astrophotonical applications
Astronomische Nachrichten, Volume 344, Issue 8-9, October-November 2023., 2023 Abstract To better understand the impact of the avalanche gain applied in the detector technology and apply this technology in our in‐house astrophotonic projects, we have characterized a C‐RED One camera and produced a stable and reliable method for calculating the system gain at any desired avalanche gain setting.
Stella Vješnica +3 more
wiley +1 more source
Fortschritte der Physik, Volume 71, Issue 8-9, September 2023., 2023 Abstract The momentum and Hamiltonian constraints of vacuum Einstein equations, within the Bowen‐York formalism, for two interacting black holes in close separation, with anti‐parallel spins and anti‐parallel linear momenta is studied. An analytical solution using perturbation theory is given.
Emel Altas, Emine Ertugrul, Bayram Tekin
wiley +1 more source
The Case for the Fundamental MBH-σ Relation
Frontiers in Physics, 2020 Strong scaling relations between host galaxy properties (such as stellar mass, bulge mass, luminosity, effective radius etc) and their nuclear supermassive black hole's mass point toward a close co-evolution.
Christopher Marsden +3 more
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