Autori: J.C.A. Miller-Jones, A. Moin, S.J. Tingay, C. Reynolds, C.J. Phillips, A.K. Tzioumis, R.P. Fender, J.N. McCallum, G.D. Nicolson, V. Tudose

Editorial: Monthly Notices of the Royal Astronomical Society , 419, p.L49, 2012.

Rezumat:

We present the first resolved imaging of the milliarcsecond-scale jets in the neutron star X-ray binary Circinus X-1, made using the Australian Long Baseline Array. The angular extent of the resolved jets is ~20 mas, corresponding to a physical scale of ~150 au at the assumed distance of 7.8 kpc. The jet position angle is relatively consistent with previous arcsecond-scale imaging with the Australia Telescope Compact Array. The radio emission is symmetric about the peak, and is unresolved along the minor axis, constraining the opening angle to be <20 degree. We observe evidence for outward motion of the components between the two halves of the observation. Constraints on the proper motion of the radio-emitting components suggest that they are only mildly relativistic, although we cannot definitively rule out the presence of the unseen, ultrarelativistic (Gamma > 15) flow previously inferred to exist in this system.

Cuvinte cheie: stars: individual: Circinus X-1, ISM: jets and outflows, radio continuum: stars, X-rays: binaries

URL: http://onlinelibrary.wiley.com/doi/10.1111/j.1745-3933.2011.01176.x/abstract