Systematic study of magnetar outbursts

TL;DR

This systematic study analyzes all known magnetar outbursts through extensive X-ray data reanalysis, revealing correlations among outburst properties and discussing implications for magnetar models.

Contribution

It provides the first comprehensive, empirical analysis of magnetar outbursts, including light curve modeling, parameter correlations, and an online database for further research.

Findings

Identified correlations between peak luminosity and decay time-scale.

Estimated characteristic decay times and energetics for all outbursts.

Developed an empirical model for outburst light curves.

Abstract

We present the results of the systematic study of all magnetar outbursts observed to date, through a reanalysis of data acquired in about 1100 X-ray observations. We track the temporal evolution of the outbursts soft X-ray spectral properties and the luminosities of the single spectral components as well as of the total emission. We model empirically all outburst light curves, and estimate the characteristic decay time-scales as well as the energetics involved. We investigate the link between different parameters (e.g. the luminosity at the peak of the outburst and in quiescence, the maximum luminosity increase, the decay time-scale and energy of the outburst, the neutron star surface dipolar magnetic field and characteristic age, etc.), and unveil several correlations among these quantities. We discuss our results in the context of the internal crustal heating and twisted bundle models for magnetar outbursts. This study is complemented by the Magnetar Outburst Online Catalogue (http://magnetars.ice.csic.es), an interactive data base where the user can plot any combination of the parameters derived in this work, and download all data.