Zobrazeno 1 - 10
of 401
pro vyhledávání: '"Abramowicz, M. A."'
Autor:
Vincent, F. H., Wielgus, M., Abramowicz, M. A., Gourgoulhon, E., Lasota, J. -P., Paumard, T., Perrin, G.
Publikováno v:
A&A 646, A37 (2021)
Context. The Event Horizon Telescope (EHT) collaboration recently obtained first images of the surroundings of the supermassive compact object M87* at the center of the galaxy M87. Aims. We want to develop a simple analytic disk model for the accreti
Externí odkaz:
http://arxiv.org/abs/2002.09226
Autor:
Vincent, F. H., Abramowicz, M. A., Zdziarski, A. A., Wielgus, M., Paumard, T., Perrin, G., Straub, O.
Context. The properties of the accretion flow surrounding the supermassive central black hole of the Galaxy, Sgr A*, will be scrutinized by the new-generation instrument GRAVITY and the Event Horizon Telescope (EHT). Developing fast, robust, and simp
Externí odkaz:
http://arxiv.org/abs/1902.01175
Autor:
Abramowicz, M. A., Lasota, J. -P.
We show that a recent assertion [arXiv:1608.01541] that gravitational wave emission can lead to a repulsive force explaining the accelerated expansion of the Universe is totally unfounded.
Comment: 2 pages, submitted to MNRAS Letters
Comment: 2 pages, submitted to MNRAS Letters
Externí odkaz:
http://arxiv.org/abs/1608.02882
We argue that if particularly powerful electromagnetic afterglows of the gravitational waves bursts will be observed in the future, this could be used as a strong observational support for some suggested quantum alternatives for black holes (e.g., fi
Externí odkaz:
http://arxiv.org/abs/1603.07830
Publikováno v:
A&A 587, A13 (2016)
At super-Eddington rates accretion flows onto black holes have been described as slim (aspect ratio $H/R \lesssim 1$) or thick (H/R >1) discs, also known as tori or (Polish) doughnuts. The relation between the two descriptions has never been establis
Externí odkaz:
http://arxiv.org/abs/1510.09152
Publikováno v:
MNRAS 2015 454: 3766-3770
In general relativity static gaseous atmospheres may be in hydrostatic balance in the absence of a supporting stellar surface, provided that the luminosity is close to the Eddington value. We construct analytic models of optically thin, spherically s
Externí odkaz:
http://arxiv.org/abs/1505.06099
Autor:
Sramkova, E., Torok, G., Kotrlova, A., Bakala, P., Abramowicz, M., Stuchlik, Z., Goluchova, K., Kluzniak, W.
Estimations of black hole spin in the three Galactic microquasars GRS 1915+105, GRO J1655-40, and XTE J1550-564 have been carried out based on spectral and timing X-ray measurements and various theoretical concepts. Among others, a non-linear resonan
Externí odkaz:
http://arxiv.org/abs/1505.02712
Autor:
Karas, V., Abramowicz, M. A.
Publikováno v:
Proceedings of RAGtime 14-16: Workshops on Black Holes and Neutron Stars (Opava, Prague, Czech Republic), Z. Stuchlik, G. Torok, and T. Pechacek, editors (Silesian University in Opava), 2014, pp. 121-128
Modified Newtonian potentials have been proposed for the description of relativistic effects acting on particles and fluids in permanent orbital motion around black holes. Here we further discuss spherically symmetric potentials like the one proposed
Externí odkaz:
http://arxiv.org/abs/1412.6832
Context. The supermassive black hole, Sagittarius (Sgr) A*, in the centre of our Galaxy has the largest angular size in the sky among all astrophysical black holes. Its shadow, assuming no rotation, spans ~ 50 microarcsec. Resolving such dimensions h
Externí odkaz:
http://arxiv.org/abs/1406.0353
Autor:
Karas, V., Bakala, P., Torok, G., Dovciak, M., Wildner, M., Wzientek, D., Sramkova, E., Abramowicz, M. A., Goluchova, K., Mazur, G. P., Vincent, F. H.
In the context of high-frequency quasi-periodic oscillation (HF QPOs) we further explore the appearance of an observable signal generated by hot spots moving along quasi-elliptic trajectories close to the innermost stable circular orbit in the Schwar
Externí odkaz:
http://arxiv.org/abs/1402.5353