Theory of quasi-spherical accretion in X-ray pulsars

@article{Shakura2011TheoryOQ,
  title={Theory of quasi-spherical accretion in X-ray pulsars},
  author={Nikolai I. Shakura and Konstantin A Postnov and Al. Yu. Kochetkova and L. Hjalmarsdotter},
  journal={Monthly Notices of the Royal Astronomical Society},
  year={2011},
  volume={420},
  pages={216-236}
}
A theoretical model for quasi-spherical subsonic accretio n onto slowly rotating magnetized neutron stars is constructed. In this model the accr eting matter subsonically settles down onto the rotating magnetosphere forming an extended quasi-static shell. This shell mediates the angular momentum removal from the rotating neutron star magnetosphere during spin-down episodes by large-scale convective motions. The accretion rate through the shell is determined by the abilit y of the plasma to… 

Figures and Tables from this paper

Quasi-Spherical Subsonic Accretion onto Magnetized Neutron Stars
A theory of quasi-spherical subsonic accretion onto slowly rotating magnetized neutron stars is presented. In this regime, the accreted matter settles with subsonic velocities onto the rotating
Quasispherical subsonic accretion in X-ray pulsars
A theoretical model is considered for quasispherical subsonic accretion onto slowly rotating magnetized neutron stars. In this regime, the accreting matter settles down subsonically onto the rotating
Theory of wind accretion
A review of wind accretion in high-mass X-ray binaries is presented. We focus attention to different regimes of quasi-spherical accretion onto the neutron star: the super- sonic (Bondi) accretion,
Wind-accreting symbiotic X-ray binaries
The properties of wind accretion in symbiotic X-ray binaries (SyXBs) consisting of red-giant and magnetized neutron star (NS) are discussed. The spin-up/spin-down torques applied to NS are derived
Wind accretion: Theory and observations
A review of wind accretion in high-mass X-ray binaries is presented. We focus on different regimes of quasi-spherical accretion onto the neutron star (NS): the supersonic (Bondi) accretion, which
Bright flares in supergiant fast X-ray transients
At steady low-luminosity states, Supergiant Fast X-ray Transients (SFXTs) can be at the stage of quasi-spherical settling accretion onto slowly rotatin g magnetized neutron stars from the
EVIDENCE FOR MAGNETO-LEVITATION ACCRETION IN LONG-PERIOD X-RAY PULSARS
Study of observed spin evolution of long-period X-ray pulsars challenges quasi-spherical and Keplerian disk accretion scenarios. It suggests that the magnetospheric radius of the neutron stars is
Understanding the coexistence of spin-up and spin-down behaviours in long-period X-ray pulsars
  • W. Wang, H. Tong
  • Physics
    Monthly Notices of the Royal Astronomical Society
  • 2020
Assuming wind-fed accretion magnetars in long-period X-ray pulsars, we calculated the rotational evolution of neutron stars. Our calculations considered the effects of magnetic field decay in
Signs of magnetic accretion in the young Be/X-ray pulsar SXP 1062
The spin behaviour of the neutron star in the newly discovered young Be/X-ray long-period pulsar SXP 1062 is discussed. The star is observed to rotate with the period of 1062 s, and spin down at the
Signs of magnetic accretion in X-ray pulsars
The spin-down mechanism of accreting neutron stars is discussedwith an application to one of the best studied X-ray pulsars GX301-2. We show that the maximum possible spin-down torque applied to a
...
...

References

SHOWING 1-10 OF 45 REFERENCES
Quasi-spherical accretion in X-ray pulsars
Quasi-spherical accretion in wind-fed X-ray pulsars is discussed. At X-ray luminosities <4 10^{36} erg/s, a hot convective shell is formed around the neutron star magnetosphere, and subsonic settling
Accretion onto magnetized neutron stars: X-ray pulsars with intermediate rotation rates
Assuming that the accreting material originates in a wind or envelope and therefore carried no net angular momentum, the Kevin-Helmholtz instability is applied to the transport of accreting plasma
Accretion by rotating magnetic neutron stars. III. Accretion torques and period changes in pulsating X-ray sources.
We use the solutions of the two-dimensional hydromagnetic equations obtained previously to calculate the torque on a magnetic neutron star accreting from a Keplerian disk. We find that the magnetic
On the Dramatic Spin-up/Spin-Down Torque Reversals in Accreting Pulsars
Dramatic torque reversals between spin-up and spin-down have been observed in half of the persistent X-ray pulsars monitored by the BATSE all-sky monitor on the Compton Gamma Ray Observatory.
Accretion onto magnetized neutron stars - Normal mode analysis of the interchange instability at the magnetopause
We describe the results of a linearized hydromagnetic stability analysis of the magnetopause of an accreting neutron star. The magnetosphere is assumed to be slowly rotating, and the plasma just
Spin-up/spin-down of magnetized stars with accretion discs and outflows
An investigation is made of disk accretion of matter onto a rotating star with an aligned dipole magnetic field. A new aspect of this work is that when the angular velocity of the star and disk
MAGNETICALLY TORQUED THIN ACCRETION DISKS
We compute the properties of a geometrically thin, steady accretion disk surrounding a central rotating, magnetized star. The magnetosphere is assumed to entrain the disk over a wide range of radii.
Accretion by magnetic neutron stars. I. Magnetospheric structure and stability.
The results of a study of accretion by a slowly rotating, magnetic neutron star when the accretion flow is approximately radial are presented. The physical processes that occur in the neighborhood of
Highly magnetized neutron star in GX 301-2
The angular momentum of matter accreting onto the neutron star produces significant spin‐up torque. Effective braking mechanism must exist to balance it in order to explain the existence of
Rapid Spin-Up Episodes in the Wind-fed Accreting Pulsar GX 301–2
The accreting pulsar GX 301-2 (P = 680 s) has been observed continuously by the large-area detectors of the Burst and Transient Source Experiment (BATSE) instrument on the Compton Gamma Ray
...
...