Pan-STARRS imaging of the x-ray source position within the ANTARES neutrino detection region
ATel #7992; S. J. Smartt (QUB), K. Chambers (IfA), K. Smith (QUB), M. Huber (IfA) on behalf of the PS1SC
on 3 Sep 2015; 20:08 UT
Credential Certification: Stephen Smartt (s.smartt@qub.ac.uk)
Subjects: Optical, X-ray, Neutrinos, Gamma-Ray Burst, Star, Transient
Further to the Swift x-ray source detection by Doric et al. (GCN 18231, ATel #7987) within the error region of the ANTARES neutrino. The x-ray source is coincident with the bright R=12.6 star USNO-B1.0 0626-0501169 (B-R=1.7 and probably a G/K-type star).
There are no detected galaxies within about 5 arcsec of the Swift x-ray position
in the Pan-STARRS1 3Pi i-band stack (to approximately i~23). The bright star is
saturated, and there are several faint sources in the wings of the PSF, none
appear to be extended galaxies. There is no history of variable objects in the
Pan-STARRS1 multi-epoch data or the Pan-STARRS Survey for Transients (PSST; Huber et al. ATel #7153) within the vicinity of the x-ray source (variability of the saturated
bright star cannot be constrained from these data)
This indicates that the Swift x-ray source is not obviously associated with an
extragalactic source. The star and x-ray source maybe a chance alignment,
but spectra and photometric monitoring of the stellar source are required to determine
its current spectral type and possible state of outburst. It would appear that a physical
association of all three (the bright star, x-rays, neutrino) is unlikely.
An image is available here (green circles are USNO B1 stars, the red region shows the
saturated pixels).
https://dl.dropboxusercontent.com/u/16114916/PS1_iband_antares_nu_xraysource.png