About the observational check of the mechanism of gamma radiation in Soft Gamma Repeaters (SGR)

TL;DR

This paper discusses the mechanisms behind gamma radiation in Soft Gamma Repeaters, proposing an observational test to differentiate between magnetic field annihilation and nuclear energy release models.

Contribution

It introduces a new observational test aimed at distinguishing the dominant energy source in SGRs, either magnetic annihilation or nuclear energy release.

Findings

Proposes an observational method to test gamma radiation mechanisms.

Highlights differences in energy sources for SGRs.

Provides a framework for future observational studies.

Abstract

Soft gamma repeaters (SGR) are identified as single neutron stars (NS) inside the Galaxy, or nearby galaxies, with sporadic transient gamma radiation. A total number of discovered SGR, including relative Anomalous X-ray pulsars (AXP), is few tens of objects. Many of them show periodic radiation, connected with NS rotation, with periods 2-12 s. The slow rotation is accompanied by small rate of loss of rotational energy, which is considerably smaller than the observed sporadic gamma ray luminosity, and is many orders less that the luminosity during giant bursts, observed in 4 SGR. Therefore the energy source is usually connected with annihilation of very strong NS magnetic field. Another model is based on release of a nuclear energy stored in the NS nonequilibrium layer. We suggest here an observational test with could distinguish between these two models.