Results 11 to 20 of about 32,361 (211)

Fundamental physics opportunities with the next-generation Event Horizon Telescope

open access: yesLiving Reviews in Relativity
The Event Horizon Telescope (EHT) Collaboration recently published the first images of the supermassive black holes in the cores of the Messier 87 and Milky Way galaxies.
Dimitry Ayzenberg   +47 more
doaj   +2 more sources

A Supermassive Black Hole in an Ultracompact Dwarf Galaxy

open access: yesNature, 2014
Ultracompact dwarf galaxies (UCDs) are among the densest stellar systems in the universe. These systems have masses up to 200 million solar masses, but half light radii of just 3-50 parsecs.
Baumgardt, Holger   +13 more
core   +3 more sources

Gravitational ringing and superradiant instabilities of the Kerr-like black holes in a dark matter halo

open access: yesEuropean Physical Journal C: Particles and Fields, 2023
Supermassive black holes from the center of galaxy may be immersed in a dark matter halo. This dark matter halo may form a “cusp” structure around the black hole and disappear at a certain distance from the black hole.
Dong Liu   +4 more
doaj   +1 more source

Investigating strong gravitational lensing effects by supermassive black holes with Horndeski gravity

open access: yesEuropean Physical Journal C: Particles and Fields, 2022
We study gravitational lensing in strong-field limit by a static spherically symmetric black hole in quartic scalar field Horndeski gravity having additional hair parameter q, evading the no-hair theorem.
Jitendra Kumar   +2 more
doaj   +1 more source

A Global Inventory of Feedback

open access: yesGalaxies, 2023
Feedback from both supermassive black holes and massive stars plays a fundamental role in the evolution of galaxies and the inter-galactic medium. In this paper, we use available data to estimate the total amount of kinetic energy and momentum created ...
Timothy M. Heckman, Philip N. Best
doaj   +1 more source

Epicyclic Oscillations around Simpson–Visser Regular Black Holes and Wormholes

open access: yesUniverse, 2021
We study epicyclic oscillatory motion along circular geodesics of the Simpson–Visser meta-geometry describing in a unique way regular black-bounce black holes and reflection-symmetric wormholes by using a length parameter l.
Zdeněk Stuchlík, Jaroslav Vrba
doaj   +1 more source

Decomposition of the central structure of NGC 2273 in the NIR: A case study

open access: yesAstronomische 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

The potsdam arrayed waveguide spectrograph: A demonstrator of a cross‐dispersed integrated photonic spectrograph developed for the astronomical H‐band

open access: yesAstronomische 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

Investigation of some galactic and extragalactic gravitational phenomena [PDF]

open access: yesSerbian 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.
doaj   +1 more source

PAWS and POCO: NIR Astrophotonic Instruments for Astronomy

open access: yesAstronomische 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
wiley   +1 more source

Home - About - Disclaimer - Privacy