The X-ray Pulsar 2A 1822-371 as a Super Eddington source
arXiv:1702.07524 · doi:10.1093/mnras/stx491
Abstract
The low mass X-ray binary 2A 1822-371 is an eclipsing system with an accretion disc corona and with an orbital period of 5.57 hr. The primary is an 0.59 s X-ray pulsar with a proposed strong magnetic field of 10^10-10^12 G. In this paper we study the spin evolution of the pulsar and constrain the geometry of the system. We find that, contrary to previous claims, a thick corona is not required, and that the system characteristics could be best explained by a thin accretion outflow due to a super-Eddington mass transfer rate and a geometrically thick inner accretion flow. The orbital, spectral and timing observations can be reconciled in this scenario under the assumption that the mass transfer proceeds on a thermal timescale which would make 2A 1822-371, a mildly super-Eddington source viewed at high inclination angles. The timing analysis on 13 years of RXTE data show a remarkably stable spin-up that implies that 2A 1822-371, might quickly turn into a millisecond pulsar in the next few thousand years.
Accepted for publication in MNRAS
References in corpus (8)
- Masses, Beaming and Eddington Ratios in Ultraluminous X-ray Sources
- "Propeller" Regime of Disk Accretion to Rapidly Rotating Stars
- ULXs: Neutron Stars vs Black Holes
- New ephemeris of the ADC source 2A 1822-371: a stable orbital-period derivative over 30 years
- A possible cyclotron resonance scattering feature near 0.7 keV in X1822-371
- Detailed study of the X-ray and Optical/UV orbital ephemeris of X1822-371
- Soft X-ray components in the hard state of accreting black holes
- Orbital and Spin Parameter Variations of Partial Eclipsing Low Mass X-ray Binary X 1822-371
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- Anomalous orbital expansion of low-mass X-ray binary 2A 1822-371: the existence of a circumbinary disk?
- On the rapid orbital expansion in the compact low-mass X-ray binary 2A 1822371
- Spectral and timing analysis of the bursting pulsar GRO J1744-28 with RXTE observations