Multi-wavelength Observations of the Radio Magnetar PSR J1622-4950 and Discovery of its Possibly Associated Supernova Remnant

TL;DR

This study presents multi-wavelength observations of the radio magnetar PSR J1622-4950, revealing its X-ray flux decay, radio variability, and potential association with a nearby supernova remnant, indicating its transient nature and possible origin from a supernova explosion.

Contribution

First detailed multi-wavelength analysis of PSR J1622-4950, identifying its transient X-ray behavior and potential link to a nearby supernova remnant, expanding understanding of magnetar environments.

Findings

X-ray flux decreased by a factor of ~50 over 3.7 years

Detected strong radio variability and possible flaring

Identified a nearby diffuse radio arc possibly being a supernova remnant

Abstract

We present multi-wavelength observations of the radio magnetar PSR J1622-4950 and its environment. Observations of PSR J1622-4950 with Chandra (in 2007 and 2009) and XMM (in 2011) show that the X-ray flux of PSR J1622-4950 has decreased by a factor of ~50 over 3.7 years, decaying exponentially with a characteristic time of 360 +/- 11 days. This behavior identifies PSR J1622-4950 as a possible addition to the small class of transient magnetars. The X-ray decay likely indicates that PSR J1622-4950 is recovering from an X-ray outburst that occurred earlier in 2007, before the 2007 Chandra observations. Observations with the Australia Telescope Compact Array show strong radio variability, including a possible radio flaring event at least one and a half years after the 2007 X-ray outburst that may be a direct result of this X-ray event. Radio observations with the Molonglo Observatory Synthesis Telescope reveal that PSR J1622-4950 is 8' southeast of a diffuse radio arc, G333.9+0.0, which appears non-thermal in nature and which could possibly be a previously undiscovered supernova remnant. If G333.9+0.0 is a supernova remnant then the estimates of its size and age, combined with the close proximity and reasonable implied velocity of PSR J1622-4950, suggests that these two objects could be physically associated.