X‐Ray Observation and Analysis of the Composite Supernova Remnant G327.1−1.1

Based on the data from the observation of the SNR G327.1-1.1 by ASCA andROSAT, we find that G327.1-1.1 is a composite remnant with both a nonthermalemission component and a diffuse thermal emission component. The nonthermalcomponent is well fitted by a power-law model with photon index about 2.2. Thiscomponent is attributed to the emission from the synchrotron nebula powered byan undiscovered central pulsar. The thermal component has a temperature ofabout 0.4 keV. We attribute it to the emission from the shock-heat swept-upISM. Its age, explosion energy and density of ambient medium are derived fromthe observed thermal component. Some charactistics about the synchrotron nebulaare also derived. We search for the pulsed signal, but has not found it. Thesoft X-ray(0.4 - 2 keV) and hard X-ray(2 - 10 keV) images are different, butthey both elongate in the SE-NW direction. And this X-ray SE-NW elongation isin positional coincidence with the radio ridge in MOST 843MHz radio map. Wepresent a possibility that the X-ray nonthermal emission mainly come from thetrail produced by a quickly moving undiscoverd pulsar, and the long radio ridgeis formed when the pulsar is moving out of the boundary of the plerionicstructure.Comment: 20 pages, 4 Postscript figures, aasms4.sty and psfig.sty, to be published in Astrophysical Journal, January 20, 1999, Vol. 51