Accretion by Isolated Neutron Stars

Abstract

Accretion of interstellar material by an isolated neutron star is discussed. The point I address here is the interaction between the accretion flow and the stellar magnetosphere. I show that the interchange instabilities of the magnetospheric boundary under the conditions of interest are basically suppressed. The entry of the material into the magnetosphere is governed by diffusion. Due to this reason the persistent accretion luminosity of isolated neutron stars is limited to < 4E+26 erg/s. These objects can also appear as X-ray bursters with the burst durations of about 30 minutes and repetition time of about 1E+5 yr. This indicates that the number of the accreting isolated neutron stars which could be observed with recent and modern X-ray missions is a few orders of magnitude smaller than that previously estimated.

3 pages, to appear in Astrophysics and Space Science, in the proceedings of "Isolated Neutron Stars: from the Interior to the Surface", edited by D. Page, R. Turolla and S. Zane

References in corpus (5)

• The Neutron Stars Census
• Log N -- Log S distributions of accreting and cooling isolated neutron stars
• On the duration of the subsonic propeller state of neutron stars in wind-fed mass-exchange close binary systems
• On the accretion luminosity of isolated neutron stars
• Period distribution of old accreting isolated neutron stars

Cited by in corpus (2)

• The isolated neutron star candidate 2XMM J104608.7-594306
• A search for thermally emitting isolated neutron stars in the 2XMMp catalogue