J 2007

Humpy LNRF-velocity profiles in accretion discs orbiting almost extreme Kerr black holes. A possible relation to quasi-periodic oscillations

SLANÝ, Petr; Zdeněk STUCHLÍK and Gabriel TÖRÖK

Basic information

Original name

Humpy LNRF-velocity profiles in accretion discs orbiting almost extreme Kerr black holes. A possible relation to quasi-periodic oscillations

Authors

Edition

Astronomy & Astrophysics, FR - Francouzská republika, 2007, 0004-6361

Other information

Language

English

Type of outcome

Article in a journal

Field of Study

10308 Astronomy

Confidentiality degree

is not subject to a state or trade secret

Impact factor

Impact factor: 4.259

Organization unit

Faculty of Philosophy and Science in Opava

DOI

UT WoS

000244229900002

EID Scopus

2-s2.0-33847754685

Keywords in English

black hole physics, accretion disks, relativity

Tags

Tags

International impact

Links

MSM4781305903, plan (intention).
Changed: 7/12/2020 10:23, Mgr. Pavlína Jalůvková

Abstract

In the original language

Change of sign of the LNRF-velocity gradient has been found for accretion discs orbiting rapidly rotating Kerr black holes with spin a > 0.9953 for Keplerian discs and a > 0.99979 for marginally stable thick discs. Aschenbach (2004) has identified the maximal rate of change of the orbital velocity within the "humpy" profile with a locally defined critical frequency of disc oscillations, but it has been done in a coordinate-dependent form. We define the critical "humpy" frequency H in general relativistic, coordinate independent form, and relate the frequency defined in the LNRF to distant observers. At radius of its definition, so-called "humpy" radius r_h, the "humpy" frequency H is compared to the radial (R) and vertical (V) epicyclic frequencies andthe orbital frequency of the disc.