A Supernova at z = 0.458 and Implications for Measuring the Cosmological Deceleration

S. Perlmutter, C. R. Pennypacker, G. Goldhaber +20

We have begun a program to discover high-redshift supernovae ($z\approx$ 0.25--0.5), and study them with follow-up photometry and spectroscopy. We report here our first discovery,…