Soderberg, A MKulkarni, Shrinivas RFox, Derek BBerger, EdoPrice, Paul AntonyCenko, Stephen BHowell, D AGal-Yam, AvishayLeonard, D CFrail, Dale AMoon, D-SChevalier, Roger AHamuy, MHurley, K CKelson, Daniel DKoviak, KKrzeminski, WKumar, PMacFadyen, AMcCarthy, P JPark, H-SPeterson, BrucePhillips, Mark MRauch, MRoth, MShectman, Stephen2015-12-132015-12-130004-637Xhttp://hdl.handle.net/1885/80257We present the results from a Hubble Space Telescope ACS search for supernovae associated with X-ray flashes 020903, 040701, 040812, and 040916. We find strong evidence that XRF 020903 (z = 0.25) was associated with a SN 1998bw-like supernova and confirmKeywords: Gamma rays: bursts; Radiation mechanisms: nonthermal; X-rays: bursts200510.1086/4304052015-12-11