Hubble Space Telescope Space Telescope Imaging Spectrograph Imaging of the Host Galaxy of GRB 980425/SN 1998BW
Tanvir, N.; Hjorth, J.; Björnsson, G.; Thomsen, B.; Fynbo, J. U.; Holland, S.; Andersen, M. I.; Natarajan, P.; Jaunsen, A. O.
Denmark, Finland, Iceland, Norway, United Kingdom, United States
Abstract
We present Hubble Space Telescope Space Telescope Imaging Spectrograph observations of ESO 184-G82, the host galaxy of the gamma-ray burst GRB 980425 associated with the peculiar Type Ic supernova SN 1998bw. ESO 184-G82 is found to be an actively star-forming SBc subluminous galaxy. We detect an object consistent with being a point source within the astrometric uncertainty of 0.018" of the position of the supernova. The object is located inside a star-forming region. The object is >~1 mag brighter than expected for the supernova based on a simple radioactive decay model. This implies either a significant flattening of the light curve or a contribution from an underlying star cluster. Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555 and on observations made with ESO Telescopes at the Paranal Observatory under program 63.O-0065.