The spectacular X-ray echo of a magnetar burst

TL;DR

This paper reports on the observation of expanding X-ray rings caused by a magnetar burst, allowing for detailed analysis of the burst, dust properties, and distance estimation of the magnetar.

Contribution

It provides the first detailed study of X-ray echo rings from a magnetar burst, including spatial, spectral evolution, and dust property constraints.

Findings

Estimated distance to the magnetar

Constraints on interstellar dust properties

Detailed spectral and spatial evolution of X-ray rings

Abstract

The Anomalous X-ray Pulsar (AXP) 1E 1547.0-5408 reactivated in 2009 January with the emission of dozens of short bursts. Follow-up observations with Swift/XRT and XMM-Newton showed the presence of multiple expanding rings around the position of the AXP. These rings are due to scattering, by different layers of interstellar dust, of a very high fluence burst emitted by 1E 1547.0-5408 on 2009 January 22. Thanks to the exceptional brightness of the X-ray rings, we could carry out a detailed study of their spatial and spectral time evolution until 2009 February 4. This analysis gives the possibility to estimate the distance of 1E 1547.0-5408. We also derived constraints on the properties of the dust and of the burst responsible for this rare phenomenon.