When the most massive stars explode as supernovas, they don't fade into the night, but sometimes glow ferociously with high-energy gamma rays. What powers these energetic stellar remains? NASA's Nuclear Spectroscopic Telescope Array, or NuSTAR, is helping to untangle the mystery. The observatory's high-energy X-ray eyes were able to peer into a particular site of powerful gamma rays and confirm the source: A spinning, dead star called a pulsar. Pulsars are one of several types of stellar remnants that are left over when stars blow up in supernova explosions. Read more
Title: XMM-Newton observations reveal the X-ray counterpart of the very-high-energy gamma-ray source HESSJ1640-465 Authors: S.Funk, J.A.Hinton, G.Puehlhofer, F.A.Aharonian, W.Hofmann, O.Reimer, S.Wagner
We present X-ray observations of the as of yet unidentified very high-energy (VHE) gamma-ray source HESSJ1640-465 with the aim of establishing a counterpart of this source in the keV energy range, and identifying the mechanism responsible for the VHE emission. The 21.8 ksec XMM-Newton observation of HESSJ1640-465 in September 2005 represents a significant improvement in sensitivity and angular resolution over previous ASCA studies in this region. These new data show a hard-spectrum X-ray emitting object at the centroid of the H.E.S.S. source, within the shell of the radio Supernova Remnant (SNR) G338.3-0.0. This object is consistent with the position and flux previously measured by both ASCA and Swift-XRT but is now shown to be significantly extended. We argue that this object is very likely the counterpart to HESSJ1640-465 and that both objects may represent the Pulsar Wind Nebula of an as of yet undiscovered pulsar associated with G338.3-0.0.