X-Ray and Radio Observations of Bright GEV Sources

We present X-ray and radio studies of sources which are bright above 1 GeV (F >GeV} ≥ 4 x 10-8ph cm-2s-1). Only 11 out of ~ 30 of these γ-ray sources have been identified with lower energy counterparts: 5 blazars and 6 pulsars. Three of these pulsars are surrounded by radio pulsar wind nebulae (PWN), two of which are also seen as bright, extended X-ray synchrotron nebulae. The ASCA X-ray telescope has observed 28 of the bright GeV sources, revealing an excess of F 2-10keV > 10-12ergs cm-2 s-1 source within the EGRET error contours of the unidentified sources. Although several supernova remnants are positionally coincident with these sources, we find no X-ray evidence of high energy particle production in SNR shell shocks consistent with the GeV positions. We also present initial results from follow on radio imaging studies of several fields containing unidentified sources. We have discovered new X-ray/radio nebulae in three of these fields which are strong candidates for PWN. These sources, along with a the PWN around PSR B1853+01 in W44, are all positionally coincident with variable EGRET sources. This suggests a class of variable γ-ray sources associated with synchrotron emitting regions powered by the winds of young pulsars.