J 2021

Dragged surfaces. On the accretion tori in the ergoregion

PUGLIESE, Daniela and Zdeněk STUCHLÍK

Basic information

Original name

Dragged surfaces. On the accretion tori in the ergoregion

Authors

PUGLIESE, Daniela (380 Italy, belonging to the institution) and Zdeněk STUCHLÍK (203 Czech Republic, belonging to the institution)

Edition

Publications Of The Astronomical Society Of Japan, England, 2021, 0004-6264

Other information

Language

English

Type of outcome

Článek v odborném periodiku

Field of Study

10308 Astronomy

Country of publisher

United Kingdom of Great Britain and Northern Ireland

Confidentiality degree

není předmětem státního či obchodního tajemství

References:

RIV identification code

RIV/47813059:19630/21:A0000149

Organization unit

Institute of physics in Opava

UT WoS

000733238200006

Keywords in English

accretion; accretion disks;black hole physics;galaxies: active;galaxies: jets;hydrodynamics

Tags

Tags

International impact, Reviewed
Změněno: 21/2/2022 15:11, Mgr. Pavlína Jalůvková

Abstract

V originále

We discuss the conditions for the existence of extended matter configurations orbiting in the ergoregion or close to the outer ergosurface of the Kerr black hole ("dragged" configurations). The co-rotating tori under consideration are perfect fluid configurations with barotropic equations of state, orbiting on the equatorial plane of the central Kerr black hole. The possibility of magnetized tori with a toroidal magnetic field is also discussed. Indications on the attractors where dragged tori can be observed are provided with the analysis of the fluid characteristics and geometrical features, relevant for the torus stability and their observations. QPO emissions from the inner edges of the dragged tori are also discussed. We argue that the smaller dragged tori could be subjected to a characteristic instability: the effect of the frame-dragging. This possibility is thoroughly explored. This can finally lead to the destruction of the torus (disk exfoliation) which can combine with accretion and processes present in the region very close to the black hole horizon. Tori are characterized according to the central attractor dimensionless spin. These structures can be observed in orbiting black holes with dimensionless spin a > 0.9897 M.