An X-ray characterization of the central region of the SNR G332.5-5.6

A. SUAREZ, J. A. COMBI, J. F. ALBACETE COLOMBO, S. PARON, F. GARCIA, M. MICELI

ASTRONOMY AND ASTROPHYSICS

EDP SCIENCES S A

Lugar: Paris; Año: 2015

0004-6361

We present an X-ray analysis of the central region of supernova remnant (SNR)G332.5-5.6 through an exhaustive analysis of XMM-Netwon observations withcomplementary infrared observations. We characterize and discuss the origin ofthe observed X-ray morphology, which presents a peculiar plane edge over thewest side of the central region. The morphology and spectral properties of theX-ray supernova remnant were studied using a single full frame XMM-Newtonobservation in the 0.3 to 10.0 keV energy band. Archival infrared WISEobservations at 8, 12 and 24 mu m were also used to investigate the propertiesof the source and its surroundings at different wavelengths. The results showthat the extended X-ray emission is predominantly soft (0.3-1.2 keV) and peaksaround 0.5 keV, which shows that it is an extremely soft SNR. X-ray emissioncorrelates very well with central regions of bright radio emission. On the westside the radio/X-ray emission displays a plane-like feature with a terminalwall where strong infrared emission is detected. Our spatially resolved X-rayspectral analysis confirms that the emission is dominated by weak atomicemission lines of N, O, Ne, and Fe, all of them undetected in previous X-raystudies. These characteristics suggest that the X-ray emission is originated inan optically thin thermal plasma, whose radiation is well fitted by anon-equilibrium ionization collisional plasma (VNEI) X-ray emission model. Ourstudy favors a scenario where G332.5-5.6 is expanding in a medium with anabrupt density change (the wall), likely a dense infrared emitting region ofdust on the western side of the source.