A scenario of the formation of isolated X-ray pulsars with anomalously long period

TL;DR

This paper proposes a formation scenario for isolated X-ray pulsars with long periods, explaining their properties through magnetic-levitation accretion from a fossil disk after binary disintegration.

Contribution

It introduces a novel evolutionary pathway for isolated X-ray pulsars involving magnetic-levitation accretion from a fossil disk post-supernova binary disintegration.

Findings

The pulsar 1E 161348-5055 can be explained by magnetic-levitation accretion.

The neutron star's parameters align with accretion from a non-Keplerian magnetic disk.

The lifetime of such isolated X-ray pulsars can reach several thousand years.

Abstract

A scenario of the formation of isolated X-ray pulsars is discussed with an application to one of the best studied objects of this class 1E 161348-5055. This moderately luminous, 10^33 - 10^35 erg/s, pulsar with a relatively soft spectrum, kT ~ 0.6-0.8 keV, is associated with an isolated neutron star, which is located near the center of the young (~2000 yr) compact supernova remnant RCW 103 and rotates steadily (|d\nu/dt| < 2.6 x 10^-18 Hz/s) with the period of 6.7 hr. We show that in the current epoch the neutron star is in the accretor state. The parameters of the source emission can be explained in terms of the magnetic-levitation accretion scenario in which the star with the surface magnetic field of 10^12 G accretes material onto its surface from a non-Keplerian magnetic fossil disk at the rate 10^14 g/s. A neutron star could evolve to this state in a High-Mass X-ray Binary (HMXB), which had disintegrated during the supernova explosion powered by the core-collapse of its massive component. The life-time of an isolated X-ray pulsar formed this way can be as long as a few thousand years.