Burst and Persistent Emission Properties during the Recent Active Episode of the Anomalous X-ray Pulsar 1E 1841-045

TL;DR

This study analyzes burst activity from the Anomalous X-ray Pulsar 1E 1841-045, revealing that bursts are short and low-energy, with no significant impact on persistent emission, suggesting a different underlying mechanism from other magnetars.

Contribution

First detailed analysis of burst and persistent emission properties of 1E 1841-045 during its recent active episode, highlighting differences from typical magnetar behavior.

Findings

Burst durations 18-140 ms, similar to other magnetars.

Burst energies between 0.8-25 x 10^38 erg, on the lower end.

No significant change in persistent flux during bursts.

Abstract

Swift/BAT detected the first burst from 1E 1841-045 in May 2010 with intermittent burst activity recorded through at least July 2011. Here we present Swift and Fermi/GBM observations of this burst activity and search for correlated changes to the persistent X-ray emission of the source. The T90 durations of the bursts range between 18-140 ms, comparable to other magnetar burst durations, while the energy released in each burst ranges between (0.8 - 25)E38 erg, which is in the low side of SGR bursts. We find that the bursting activity did not have a significant effect on the persistent flux level of the source. We argue that the mechanism leading to this sporadic burst activity in 1E 1841-045 might not involve large scale restructuring (either crustal or magnetospheric) as seen in other magnetar sources.