Tuesday, September 26, 2017

SRL Sack Lunch Seminar, 11 am, 273 Cahill

"The Swift Bulge Survey - in search of the faintest X-ray transients," Aaron Shaw, University of Alberta

Abstract: Very Faint X-ray Transients (VFXTs) show peak X-ray luminosities in the range 10E(34-36) erg/s. The luminosities of these sources implies an extremely low time-averaged accretion rate, which remains difficult to explain in the context of binary evolution models. Of order 20 VFXTs are known, but few have multi-wavelength studies to constrain the donor star, and the total size of the population is not well known. We have recently initiated the Swift Bulge Survey (SBS), a wide, shallow Swift/XRT imaging survey of 16 square degrees of the Galactic Bulge, to be performed fortnightly for 15 epochs, with the intention of uncovering a number of new VFXTs over the course of the survey. Here I will delve into the relatively short history of VFXTs and report on the results from the first phase of the SBS. I will detail the multi-wavelength follow-up of sources discovered in the SBS, as well as the first multi-band NIR photometry of previously known VFXTs in an attempt to place constraints on their counterparts and investigate the nature of accretion in these systems.