Hintze Centre for Astrophysical Surveys

Abstract:

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 ∼20mas, corresponding to a physical scale of ∼150au at the assumed distance of 7.8kpc. 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°. 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 (Γ > 15) flow previously inferred to exist in this system. © 2011 The Authors Monthly Notices of the Royal Astronomical Society © 2011 RAS.

Abstract:

The search for transient phenomena in the Universe has entered a new era. In the next decade new all-sky surveys will provide a vast amount of astronomical survey data. These data will address issues in many of the astronomical fields. In the Supernova field, we will have for the first time the possibility to discover SNe without most of the observational bias present in the previous SN searches. Here we report the status of the transients study in one of the new on-going all-sky surveys: the Panoramic Survey Telescope & Rapid Response System-1 (PanStarrs-1).