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Mass Functions of Supermassive Black Holes across Cosmic Time [PDF]
Advances in Astronomy, 2012 The black hole mass function of supermassive black holes describes the evolution of the distribution of black hole mass. It is one of the primary empirical tools available for mapping the growth of supermassive black holes and for constraining ...
Brandon C. Kelly, Andrea Merloni
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Black hole shadow with a cosmological constant for cosmological observers
European Physical Journal C: Particles and Fields, 2019 We investigate the effect of the cosmological constant on the angular size of a black hole shadow. It is known that the accelerated expansion which is created by the cosmological constant changes the angular size of the black hole shadow for static ...
Javad T. Firouzjaee, Alireza Allahyari
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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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The ngEHT’s Role in Measuring Supermassive Black Hole Spins
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
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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
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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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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
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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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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