CYBERSKA

 A Cyberinfrastructure platform to meet the needs of data intensive radio astronomy on route to the SKA

Detection of Jet-like Radio Emission Associated to Geminga

  • Public
By Samuel George 4138 days ago
http://arxiv.org/abs/1102.4754

A deep Very Large Array observation of the Geminga pulsar field led to the discovery, at a higher than 10sigma significance level, of radio emission trailing the neutron star proper motion. This 10arcsec-long radio feature, detected with a flux of about 0.4 mJy at 4.8 GHz, is positionally coincident with the X-ray axial tail ascribed to the pulsar wind nebula recently discovered by Chandra. We discuss the implications of the radio emission in the frames of both shocked pulsar wind collimated by the ram pressure and jet models. Taking into account the pulsar proper motion and outflow velocity, the X-ray and radio synchrotron cooling times, compared with the tail size, constrain the magnetic field within the radio structure in the range 0.05-10 G, uncomfortably fitting in standard pulsar bow-shock models, but compatible with the parameters of the jets typically observed in microquasars. The Geminga axial tail could represent the first radio jet clearly associated to an isolated neutron star and its detection was possible due to the proximity of the pulsar and its radio-quiet nature, not hindering the radio structure.