The Long-term Radiative Evolution of Anomalous X-ray Pulsar 1E 2259+586 after its 2002 Outburst

TL;DR

This paper analyzes X-ray observations of AXP 1E 2259+586 post-2002 outburst, revealing flux decay, temperature changes, and a flux-hardness correlation, informing magnetar models.

Contribution

It provides a detailed long-term observational study of AXP 1E 2259+586's radiative evolution after its outburst, highlighting flux decay and spectral changes.

Findings

Flux decay follows a power-law with index -0.69

Source remained hotter and brighter than preoutburst as of 2005

Strong correlation between spectral hardness and flux

Abstract

We present an analysis of five X-ray Multi-Mirror Mission (XMM) observations of the anomalous X-ray pulsar (AXP) 1E 2259+586 taken in 2004 and 2005 during its relaxation following its 2002 outburst. We compare these data with those of five previous XMM observations taken in 2002 and 2003, and find the observed flux decay is well described by a power-law of index -0.69+/-0.03. As of mid-2005, the source may still have been brighter than preoutburst, and was certainly hotter. We find a strong correlation between hardness and flux, as seen in other AXP outbursts. We discuss the implications of these results for the magnetar model.