Hubble Space Telescope and Ground-Based Observations of Type Ia Supernovae at Redshift 0.5: Cosmological Implications
Abstract
We present observations of the Type Ia supernovae (SNe) 1999M, 1999N, 1999Q, 1999S, and 1999U, at redshift z~0.5. They were discovered in early 1999 with the 4.0~m Blanco telescope at Cerro Tololo Inter-American Observatory by the High-z Supernova Search Team (HZT) and subsequently followed with many ground-based telescopes. SNe 1999Q and 1999U were also observed with the Hubble Space Telescope. We computed luminosity distances to the new SNe using two methods, and added them to the high-z Hubble diagram that the HZT has been constructing since 1995. The new distance moduli confirm the results of previous work. At z~0.5, luminosity distances are larger than those expected for an empty universe, implying that a ``Cosmological Constant,'' or another form of ``dark energy,'' has been increasing the expansion rate of the Universe during the last few billion years.
Keywords
Cite
@article{arxiv.astro-ph/0510155,
title = {Hubble Space Telescope and Ground-Based Observations of Type Ia Supernovae at Redshift 0.5: Cosmological Implications},
author = {A. Clocchiatti and B. Schmidt and A. Filippenko and P. Challis and A. Coil and R. Covarrubias and A. Diercks and P. Garnavich and L. Germany and R. Gilliland and C. Hogan and S. Jha and R. Kirshner and B. Leibundgut and D. Leonard and W. Li and T. Matheson and M. Phillips and J. Prieto and D. Reiss and A. Riess and R. Schommer and R. Smith and A. Soderberg and J. Spyromilio and C. Stubbs and N. Suntzeff and J. Tonry and P. Woudt},
journal= {arXiv preprint arXiv:astro-ph/0510155},
year = {2019}
}
Comments
68 pages, 22 figures. Scheduled for the 01 February 2006 issue of Ap.J. (v637)