Multi-wavelength Observations of the Radio Magnetar PSR J1622-4950 and Discovery of Its Possibly Associated Supernova Remnant
Esposito, Paolo; Rea, Nanda; Drake, Jeremy J.; Chakrabarty, Deepto; Lee, Julia C.; Israel, G. L.; Kaplan, David L.; Lazio, T. Joseph W.; Gaensler, B. M.; Levin, Lina; Kramer, Michael; Hong, Jaesub; Mauerhan, Jon C.; Murray, Stephen S.; Johnston, Simon; Burke-Spolaor, Sarah; Slane, Patrick O.; Grindlay, Jonathan E.; Benjamin, Robert A.; Possenti, Andrea; Posselt, Bettina; Bailes, Matthew; Burgay, Marta; Anderson, Gemma E.; Brogan, Crystal L.; D'Amico, Nichi; Steeghs, Danny T. H.; Bates, Samuel; Bhat, N. D. Ramesh; Keith, Michael J.; Milia, Sabrina; Stappers, Ben
Australia, United States, Spain, United Kingdom, Italy, Germany
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 τ = 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 (SNR). If G333.9+0.0 is an SNR then the estimates of its size and age, combined with the close proximity and reasonable implied velocity of PSR J1622-4950, suggest that these two objects could be physically associated.