Neutron star high mass binaries as the origin of SGR/AXP

TL;DR

This paper proposes that high-mass binary systems with neutron stars can evolve into Thorne-Żytkow objects, which then explain the origins of soft gamma-ray repeaters and anomalous X-ray pulsars through their explosive and contraction phases.

Contribution

It introduces a new evolutionary scenario linking neutron star binaries to specific high-energy astrophysical phenomena, supported by computational modeling.

Findings

TZO formation tracks are calculated using the scenario machine program.

Explosive contraction of TZO leads to soft gamma-ray repeaters.

Stellar remnants of TZO evolution can be anomalous X-ray pulsars.

Abstract

A close high-mass binary system consisting of a neutron star (NS) and a massive OB supergiant companion is expected to lead to a TZO structure, which consists of a NS core and a stellar envelope. We use the scenario machine program to calculate the formation tracks of TZOs in close high mass NS binaries and their subsequent evolution. We propose and demonstrate that the explosion and instant contraction of a TZO structure leave its stellar remnant as a soft gamma ray repeater and an anomalous X-ray pulsar respectively.