The Position of ASASSN-14ha is Consistent with a Red Extended Source in HST Pre-Explosion Images
ATel #6476; C. McCully, I. Arcavi, S. Valenti, G. Hosseinzadeh and D. A. Howell (LCOGT)
on 15 Sep 2014; 23:26 UT
Credential Certification: Iair Arcavi (iarcavi@lcogt.net)
Subjects: Optical, Supernovae
We obtained photometry of the supernova ASASSN-14ha using one the LCOGT 1m telescopes at Siding Spring on 2014 September 14 (UT) with 1.18" FWHM seeing. We registered this image to the HST pre-explosion images of NGC 1566 taken with the ACS camera (Program 12999; PI Foley). The RMS of the fit was 0.07" using nine overlapping unsaturated sources. We find that the position of the SN is consistent with (albeit on the edge of) an extended source, possibly a star cluster. The source is elongated in the East-West direction and has a FWHM 25% larger than typical stars in the field. There are no other detected sources within 3-sigma of the SN position (see image). We measured the photometry of the object in the pre-explosion images using SExtractor, reporting the MAG_BEST and MAGERR_BEST as the magnitude and uncertainty. The source is red with 21.924 +- 0.0023 in F435W (B), 21.930+-0.0031 in F555W (V), 21.734 +- 0.0028 in F625W (R), and 21.092 +- 0.0023 in F814W (I).
