Pre- and post-explosion images of the site of SN 2003gd

(from Science Express paper): Pre- and post-explosion images of the site of SN 2003gd taken with the HST WFPC2 and Gemini GMOS instruments (see Table 1 for details). (A) Pre-explosion WFPC2 F606W image, with the previously identified progenitor object marked as Star A, and a nearby star labelled Star C. (B) Pre-explosion Gemini GMOS i band image, with spatial resolution 0.57”, in which the progenitor is detected. (C) Post-explosion Gemini GMOS i band image where a single point source is not detected at the transformed position of SN 2003gd, with a limit on any remaining SN flux of mi (AB) > 26.3. The image has a spatial resolution of 0.36” and no point source is detected at the position of Star C, suggesting a negligible contribution in the i-band from that star. (D) Pre-explosion image with the flux/PSF-scaled post-explosion image subtracted. The residual object at the position of SN 2003gd is the progenitor, with any contaminating flux from nearby stars subtracted. The object at the SN location, marked as Star A, is consistent with single-star PSF (χ2 = 0.9) and has a Johnson-I magnitude 23.14 ± 0.08 (mi (AB) = 24.25 ± 0.04). In the bottom right hand corner a model single star PSF is shown. It was determined by IS IS and is consistent with the source detected in this subtraction image.