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The Usefulness of Type Ia Supernovae for Cosmology--a Personal Review

Volume 40 number 1 (2012)

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Kevin Krisciunas
George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy, Department of Physics and Astronomy, Texas A & M University, 4242 TAMU, College Station, TX 77843; krisciunas@physics.tamu.edu

Abstract

We review some results of the past twelve years derived from optical and infrared photometry of Type Ia supernovae. A combination of optical and infrared photometry allows us to determine accurately the extinction along the line of sight. The resulting distance measurements are much more accurate than can be obtained from optical data alone. Type Ia supernovae are very nearly standard candles in the near-infrared. Accurate supernova distances, coupled with other observational data available at present, allow us to determine the matter density in the universe and lead to evidence for the existence of Dark Energy. We can now address some questions on the grandest scale such as, “What is the ultimate Fate of the universe?”