Modelling of 35-d superorbital cycle of B and V light curves of IMXB HZ Her/Her X-1-Reference-Cited by-同舟云学术

Modelling of 35-d superorbital cycle of B and V light curves of IMXB HZ Her/Her X-1

Published:2020-10-12 Issue:2 Volume:499 Page:1747-1757
ISSN:0035-8711
Container-title:Monthly Notices of the Royal Astronomical Society
language:en
Short-container-title:

Author:

Kolesnikov D A¹^ORCID,Shakura N I¹²,Postnov K A¹²^ORCID,Volkov I M¹³,Bikmaev I F²⁴,Irsmambetova T R¹,Staubert R⁵,Wilms J⁶,Irtuganov E²⁴,Golysheva P Yu¹,Shugarov S Yu¹⁷,Nikolenko I V³⁸,Trunkovsky E M¹,Schönherr G⁹,Schwope A⁹,Klochkov D⁵

Affiliation:

1. Sternberg Astronomical Institute, Moscow State University, 119234 Moscow, Russia

2. Kazan Federal University, 420008 Kazan, Russia

3. Institute of Astronomy RAS, 119017 Moscow, Russia

4. Academy of Sciences of Tatarstan, 420111 Kazan, Russia

5. Institute for Astronomy and Astrophysics, D-72074 Tubingen, Germany

6. Astronomical Institute of the University of Erlangen-Nuremberg, D-96049 Bamberg, Germany

7. Astronomical Institute of the Slovak Academy of Scienses, 18 059 60 Tatranska Lomnica, Slovakia

8. Crimean Astrophysical Observatory, 298409 Nauchny, Russia

9. Leibniz Institute for Astrophysics, D-14482 Potsdam, Germany

Abstract

ABSTRACT The X-ray binary Her X-1 consists of an accreting neutron star and the optical component HZ Her. The 35-d X-ray superorbital variability of this system is known, since its discovery in 1972 by the Uhuru satellite and is believed to be caused by forced precession of a warped accretion disc tilted to the orbital plane. We argue that the observed features of the 35-d optical variability of HZ Her can be explained by free precession of the neutron star with a period close to that of the forced disc. The model parameters include (a) the X-ray luminosity of the neutron star; (b) the optical flux from the accretion disc; and (c) the tilt of the inner and outer edges of the accretion disc. A possible synchronization mechanism based on the coupling between the neutron star free precession and the dynamical action of non-stationary gas streams is discussed.

Funder

Russian Foundation for Basic Research

California Department of Fish and Game

Publisher

Oxford University Press (OUP)

Subject

Space and Planetary Science,Astronomy and Astrophysics

Link

http://academic.oup.com/mnras/advance-article-pdf/doi/10.1093/mnras/staa2829/33865746/staa2829.pdf

Reference65 articles.

1. Spectra of Hercules X-1 near a turn-on in the 35 day cycle

2. Color photometric study of HZ Her.