A parsec scale X-ray extended structure from the X-ray binary Circinus   X-1
  We present the results of the analysis of two Chandra observations of Circinus X-1 performed in 2007, for a total exposure time of ~50 ks. The source was observed with the High Resolution Camera during a long X-ray low-flux state of the source. Cir X-1 is an accreting neutron-star binary system that exhibits ultra-relativistic arcsec-scale radio jets and an extended arcmin-scale radio nebula. Furthermore, a recent paper has shown an X-ray excess on arcmin-scale prominent on the side of the receding radio jet. In our images we clearly detect X-ray structures both on the side of the receding and the approaching radio jet. The X-ray emission is consistent with being from synchrotron origin. Our detection is consistent with neutron-star binaries being as efficient as black-hole binaries in producing X-ray outflows, despite their shallower gravitational potential. 
P. Soleri (1), S. Heinz (2), R. Fender (3), R. Wijnands (1), V. Tudose   (1), D. Altamirano (1), P.G. Jonker (4,5), M. van d...