As part of a multiwavelength study of the unusual radio supernova remnant DA 495 , we present observations made with the Chandra X-ray Observatory .
Imaging and spectroscopic analysis confirms the previously detected X-ray source at the heart of the annular radio nebula , establishing the radiative properties of two key emission components : a soft unresolved source with a blackbody temperature of 1 MK consistent with a neutron star , surrounded by a nonthermal nebula 40 ^ { \prime \prime } in diameter exhibiting a power-law spectrum with photon index \Gamma = 1.6 \pm 0.3 , typical of a pulsar wind nebula .
The implied spin-down luminosity of the neutron star , assuming a conversion efficiency to nebular flux appropriate to Vela-like pulsars , is \sim 10 ^ { 35 } ergs s ^ { -1 } , again typical of objects a few tens of kyr old .
Morphologically , the nebular flux is slightly enhanced along a direction , in projection on the sky , independently demonstrated to be of significance in radio polarization observations ; we argue that this represents the orientation of the pulsar spin axis .
At smaller scales , a narrow X-ray feature is seen extending out 5 ^ { \prime \prime } from the point source , a distance consistent with the sizes of resolved wind termination shocks around many Vela-like pulsars .
Finally , we argue based on synchrotron lifetimes in the estimated nebular magnetic field that DA 495 represents a rare pulsar wind nebula in which electromagnetic flux makes up a significant part , together with particle flux , of the neutron star ’ s wind , and that this high magnetization factor may account for the nebula ’ s low luminosity .