We report on the formation and evolution of a large-scale, synchrotron-emitting jet from the black hole candidate and X-ray binary system GX 339-4. In 2002 May, the source moved from a low/hard to a very high X-ray state, contemporaneously exhibiting a very bright optically thin radio flare. Further observations with the Australia Telescope Compact Array have tracked the formation of a collimated structure extending to about 12 arcsec, with apparent velocity greater than 0.9c. The luminosity of the outflow seems to be rapidly decreasing; these observations confirm that transient large-scale jets are likely to be common events triggered by X-ray state transitions in black hole X-ray binaries.
@article{arxiv.astro-ph/0311452,
title = {A transient large-scale relativistic radio jet from GX 339-4},
author = {Elena Gallo and Stephane Corbel and Rob Fender and Tom Maccarone and Tasso Tzioumis},
journal= {arXiv preprint arXiv:astro-ph/0311452},
year = {2009}
}