8754( 1) - 12/30/99 13:04 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 8754 Version: 1 Check-in Date: 30-Dec-1999 12:32:19 1.Proposal Title: Probing the Nature of Supernovae through Archival Images of their Environments ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle AR 9 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: Alex Filippenko University of California at Berkeley CoI: Dr. Weidong Li University of California at Berkeley N CoI: Dr. Schuyler Van Dyk Infrared Processing and Analysis Center N ------------------------------------------------------------------------------------ 5. Abstract The locations of supernovae (SNe) in the local stellar and gaseous environment in galaxies, as measured in high spatial resolution WFPC2 images, contain important clues to their progenitor stars. They provide accurate determinations of any association of SNe with H II regions or star clusters. In cases where multi-filter observations are available, we can determine the local stellar environment and search for possible attenuation of the SN by dust in the host galaxy. By checking the fields for background sources, we can correct the existing SN light curves and luminosities if necessary. When a SN has been observed incidentally, information can be gained on its optical and UV emission. Deep HST images can be used to find light echoes of SNe, as well as recover SNe interacting with circumstellar material at very late times. A direct search for the progenitor stars of SNe can be made in pre- existing HST images of their locations. In Cycle 9 we plan to extend our very successful work from previous cycles. A major improvement is that accurate ground- based coordinates are now available for numerous SNe. There are images of many host galaxies in the large and ever-growing HST archive. ------------------------------------------------------------------------------------ 8754( 1) - 12/30/99 13:04 - [ 2] Summary Form for Proposal 8754 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category AR ------------------------------------------------------------------------------------------------------------------------------------