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arXiv · astro-ph/9505023

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

S. Perlmutter·C. R. Pennypacker·G. Goldhaber·A. Goobar·R. A. Muller·H. J. M. Newberg·J. Desai·A. G. Kim·M. Y. Kim·I. A. Small·B. J. Boyle·C. S. Crawford·R. G. McMahon·P. S. Bunclark·D. Carter·M. J. Irwin·R. J. Terlevich·R. S. Ellis·K. Glazebrook·W. J. Couch·J. R. Mould·T. A. Small·R. G. Abraham
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Abstract

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, a supernova at $z = 0.458$. The photometry for this supernova closely matches the lightcurve calculated for this redshift from the template of well-observed nearby Type Ia supernovae. We discuss the measurement of the deceleration parameter $q_0$ using such high-redshift supernovae, and give the best fit value assuming this one supernova is a normal, unextincted Type Ia. We describe the main sources of error in such a measurement of $q_0$, and ways to reduce these errors.

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S. Perlmutter, C. R. Pennypacker, G. Goldhaber, A. Goobar, R. A. Muller, H. J. M. Newberg, J. Desai, A. G. Kim, M. Y. Kim, I. A. Small, B. J. Boyle, C. S. Crawford, R. G. McMahon, P. S. Bunclark, D. Carter, M. J. Irwin, R. J. Terlevich, R. S. Ellis, K. Glazebrook, W. J. Couch, J. R. Mould, T. A. Small, R. G. Abraham. 1995-05-04. A Supernova at z = 0.458 and Implications for Measuring the Cosmological Deceleration. https://doi.org/10.1086/187756

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