2021
Dragged surfaces. On the accretion tori in the ergoregion
PUGLIESE, Daniela and Zdeněk STUCHLÍKBasic 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
Article in a journal
Field of Study
10308 Astronomy
Country of publisher
United Kingdom of Great Britain and Northern Ireland
Confidentiality degree
is not subject to a state or trade secret
References:
Impact factor
Impact factor: 3.310
RIV identification code
RIV/47813059:19630/21:A0000149
Organization unit
Institute of physics in Opava
UT WoS
000733238200006
EID Scopus
2-s2.0-85122462049
Keywords in English
accretion; accretion disks;black hole physics;galaxies: active;galaxies: jets;hydrodynamics
Tags
International impact, Reviewed
Changed: 21/2/2022 15:11, Mgr. Pavlína Jalůvková
Abstract
In the original language
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.