English

23 High Redshift Supernovae from the IfA Deep Survey: Doubling the SN Sample at z>0.7

Astrophysics 2009-11-10 v1

Abstract

We present photometric and spectroscopic observations of 23 high redshift supernovae spanning a range of z=0.34-1.03, 9 of which are unambiguously classified as Type Ia. These supernovae were discovered during the IfA Deep Survey, which began in September 2001 and observed a total of 2.5 square degrees to a depth of approximately m=25-26 in RIZ over 9-17 visits, typically every 1-3 weeks for nearly 5 months, with additional observations continuing until April 2002. We give a brief description of the survey motivations, observational strategy, and reduction process. This sample of 23 high-redshift supernovae includes 15 at z>0.7, doubling the published number of objects at these redshifts, and indicates that the evidence for acceleration of the universe is not due to a systematic effect proportional to redshift. In combination with the recent compilation of Tonry et al. (2003), we calculate cosmological parameter density contours which are consistent with the flat universe indicated by the CMB (Spergel et al. 2003). Adopting the constraint that Omega_total = 1.0, we obtain best-fit values of (Omega_m, Omega_Lambda)=(0.33, 0.67) using 22 SNe from this survey augmented by the literature compilation. We show that using the empty-beam model for gravitational lensing does not eliminate the need for Omega_Lambda > 0. Experience from this survey indicates great potential for similar large-scale surveys while also revealing the limitations of performing surveys for z>1 SNe from the ground.

Keywords

Cite

@article{arxiv.astro-ph/0310843,
  title  = {23 High Redshift Supernovae from the IfA Deep Survey: Doubling the SN Sample at z>0.7},
  author = {Brian J. Barris and John Tonry and Stephane Blondin and Peter Challis and Ryan Chornock and Alejandro Clocchiatti and Alexei Filippenko and Peter Garnavich and Stephen Holland and Saurabh Jha and Robert Kirshner and Kevin Krisciunas and Bruno Leibundgut and Weidong Li and Thomas Matheson and Gajus Miknaitis and Adam Riess and Brian Schmidt and R. Chris Smith and Jesper Sollerman and Jason Spyromilio and Christopher Stubbs and Nicholas Suntzeff and H. Aussel and K. C. Chambers and M. S. Connelley and D. Donovan and J. P. Henry and N. Kaiser and M. C. Liu and E. L. Martin and R. J. Wainscoat},
  journal= {arXiv preprint arXiv:astro-ph/0310843},
  year   = {2009}
}

Comments

67 pages, 12 figures, 12 tables, accepted for publication in the Astrophysical Journal