The Power in the Ring: Timing and Spectroscopy of the Central Engine in DA 495

Observations with ROSAT, ASCA, and Chandra have revealed the existence ofVelalike pulsar+windnebula Xray emission from within the unusual radio nebulaDA 495. The evidence suggests that DA 495 is a rare example of an agingplerionic.. supernova remnant. Direct constraints on the system.s age have notbeen achievablenone of the past observations has been capable of detectingpulsations. Similarly, the energetics of the engine driving the Xray and radionebulosities are poorly constrained. We propose a 50 ksec XMM observation of DA495 to search for pulsations and obtain highquality spectra of both thepointlike and diffuse emission components, to better understand this object andthe observationally unexplored aging process for plerionic SNRs. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]