Measuring Cosmic Deceleration and Global Curvature from Observations of Distant Supernovae

Session 108 - Cosmology and Distance Indicators.
Oral session, Thursday, January 16
Frontenac Ballroom,

[108.05] Measuring Cosmic Deceleration and Global Curvature from Observations of Distant Supernovae

B. P. Schmidt (MSSSO), N. B. Suntzeff, M. Phillips, R. Schommer, A. Clocchiatti (CTIO), R. P. Kirshner, P. Garnavich, P. Challis (Harvard), B. Leibundgut, J. Spyromilio (ESO), C. Hogan, C. Stubbs, D. Reiss, A. Diercks (UW), A. Filippenko, A. Reiss (Berkeley), C. Smith (Michigan), M. Hamuy (Arizona), R. Gilliland (STScI), J. Tonry (Hawaii)

The High-Z SN Search is an international collaboration to discover and follow SNe Ia at z > 0.2 with the aim of tracing out cosmic deceleration and global curvature. This project has discovered 37 supernovae (0.09 < z < 0.84) using the Blanco 4-meter telescope at CTIO over the past two years. We have obtained spectra and two color photometry for most of these supernovae and find that 25 of the objects are SNe Ia useful for measuring distances. Using the extensive nearby set of supernovae gathered by members of our group, we demonstrate that it is possible to overcome problems associated with K-corrections, Malmquist Bias, extinction, and evolution which could affect the distances derived from SNe Ia. In addition to the SNe Ia, the search has uncovered several normal Type II supernovae on which the Expanding Photosphere can be applied, several Kuiper Belt asteroids, and a few short duration events of unknown origin.

Program listing for Thursday