Presentation #551.07 in the session “Supernova”.
We constrain the UV emission and circumstellar environment of 1455 Type Ia supernovae (SNe Ia) with z<0.5 using archival data from the Galaxy Evolution Explorer (GALEX) spacecraft. We report UV detections of four normal SNe Ia near maximum light and present comparisons to published data. We find no evidence of interaction with circumstellar medium (CSM) in our sample, and we use our nondetection rate to constrain the fraction of SNe Ia with late-onset CSM interaction. The fraction and character of these events give us a unique insight into the progenitors of SNe Ia, which are not yet fully understood.