GMRT observations of the radio trail from CXOU J163802.6-471358

The X-ray source CXOU J163802.6-471358 is thought to be a pulsar wind nebula (PWN), as it shows an extended, ≈40 arcsec trail from a compact source. Here, we present Giant Metrewave Radio Telescope observations of this source at 330 and 1390 MHz, which reveal a remarkable linear radio trail ≈90 arcsec in extent. Although the radio trail points back to the supernova remnant (SNR) G338.1+0.4, ≈50 arcmin from CXOU J163802.6-471358, associating it with this remnant would require a very large velocity for the pulsar. There are no known Galactic SNRs close to the PWN and radio trail. No pulsar has yet been identified in CXOU J163802.6-471358, but if one could be found, this would allow more quantitative studies of the PWN and radio trail to be made.