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

Edition

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

Other information

Language

English

Type of outcome

Článek v odborném periodiku

Field of Study

10308 Astronomy

Confidentiality degree

není předmětem státního či obchodního tajemství

Organization unit

Faculty of Philosophy and Science in Opava

UT WoS

000244229900002

Keywords in English

black hole physics, accretion disks, relativity

Tags

International impact

Links

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

Abstract

V originále

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.