J 2020

Models of high-frequency quasi-periodic oscillations and black hole spin estimates in Galactic microquasars

KOTRLOVÁ, Andrea, Eva ŠRÁMKOVÁ, Gabriel TÖRÖK, Kateřina GOLUCHOVÁ, Jiří HORÁK et. al.

Basic information

Original name

Models of high-frequency quasi-periodic oscillations and black hole spin estimates in Galactic microquasars

Authors

KOTRLOVÁ, Andrea (203 Czech Republic, belonging to the institution), Eva ŠRÁMKOVÁ (203 Czech Republic, belonging to the institution), Gabriel TÖRÖK (203 Czech Republic, belonging to the institution), Kateřina GOLUCHOVÁ (203 Czech Republic, belonging to the institution), Jiří HORÁK (203 Czech Republic), Odele STRAUB (756 Switzerland, belonging to the institution), Debora LANČOVÁ (203 Czech Republic, belonging to the institution), Zdeněk STUCHLÍK (203 Czech Republic, belonging to the institution) and Marek ABRAMOWICZ (616 Poland, belonging to the institution)

Edition

Astronomy & Astrophysics, FR - Francouzská republika, 2020, 0004-6361

Other information

Language

English

Type of outcome

Článek v odborném periodiku

Field of Study

10308 Astronomy

Country of publisher

France

Confidentiality degree

není předmětem státního či obchodního tajemství

References:

URL

RIV identification code

RIV/47813059:19630/20:A0000010

Organization unit

Institute of physics in Opava

DOI

http://dx.doi.org/10.1051/0004-6361/201937097

UT WoS

000588072000002

Keywords in English

X-rays: binaries; black hole physics; accretion; accretion disks

Tags

, FÚ2020, GA17-16287S, LTI17018, RIV21, SGS12-2019, SGS13-2019

Tags

International impact, Reviewed

Links

GA17-16287S, research and development project. LTI17018, research and development project.
Změněno: 31/3/2022 17:35, doc. RNDr. Jiří Kovář, Ph.D.

Abstract

V originále

We explore the influence of nongeodesic pressure forces present in an accretion disc on the frequencies of its axisymmetric and nonaxisymmetric epicyclic oscillation modes. We discuss its implications for models of high-frequency quasi-periodic oscillations (QPOs), which have been observed in the X-ray flux of accreting black holes (BHs) in the three Galactic microquasars, GRS 1915+105, GRO J1655-40, and XTE J1550-564. We focus on previously considered QPO models that deal with low-azimuthal-number epicyclic modes, |m| <= 2, and outline the consequences for the estimations of BH spin, a is an element of [0, 1]. For four out of six examined models, we find only small, rather insignificant changes compared to the geodesic case. For the other two models, on the other hand, there is a significant increase of the estimated upper limit on the spin. Regarding the falsifiability of the QPO models, we find that one particular model from the examined set is incompatible with the data. If the spectral spin estimates for the microquasars that point to a> 0.65 were fully confirmed, two more QPO models would be ruled out. Moreover, if two very different values of the spin, such as a approximate to 0.65 in GRO J1655-40 and a approximate to 1 in GRS 1915+105, were confirmed, all the models except one would remain unsupported by our results. Finally, we discuss the implications for a model that was recently proposed in the context of neutron star (NS) QPOs as a disc-oscillation-based modification of the relativistic precession model. This model provides overall better fits of the NS data and predicts more realistic values of the NS mass compared to the relativistic precession model. We conclude that it also implies a significantly higher upper limit on the microquasar's BH spin (a similar to 0.75 vs. a similar to 0.55).
Displayed: 29/12/2024 14:06