Using HST: Looking Inside SN 1987A and Making Better Measures of Cosmic Expansion

The Hubble Space Telescope has been the perfrect tool for studying SN 1987A, providing a way to dissect the expansion geometry and infer the 3D distribution of the stellar debris that was ejected 31 years ago.  Together with radio and x-ray observations, the HST data provide stringent limits on emission from the neutron star that was formed in the collapse.  HST is also a powerful tool for making rest-frame infrared observations of distant supernovae to measure cosmic expansion history.  The obvious advanatage is that infrared observations suffer less from extinction in the supernova host, but nature has been very kind and exploding white dwarfs are better standard candles in the near infrared.  I will show new results from our analysis of the world's low-red shift sample and give a report on our RAISIN program to use SNIA in the IR to constrain dark energy perperties.

Speaker: Bob Kirshner, Harvard