NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-05-20 T01:05:04 PDT
Help | Comment | NED Home

For refcode 2003ApJ...590..944W:
Retrieve 96 NED objects in this reference.
Please click here for ADS abstract

NED Abstract

Copyright by American Astronomical Society. Reproduced by permission
2003ApJ...590..944W Multicolor Light Curves of Type Ia Supernovae on the Color-Magnitude Diagram: A Novel Step toward More Precise Distance and Extinction Estimates Wang, Lifan; Goldhaber, Gerson; Aldering, Greg; Perlmutter, Saul Abstract. We show empirically that fits to the color-magnitude relation of Type Ia supernovae (SNe Ia) after optical maximum can provide accurate relative extragalactic distances. We report the discovery of an empirical color relation for SN Ia light curves: during much of the first month past maximum, the magnitudes of SNe Ia defined at a given value of color index have a very small magnitude dispersion; moreover, during this period the relation between B magnitude and B-V color (or B-R or B-I color) is strikingly linear, to the accuracy of existing well-measured data. These linear relations can provide robust distance estimates, in particular, by using the magnitudes when the SN reaches a given color. After correction for light-curve stretch factor or decline rate, the dispersion of the magnitudes taken at the intercept of the linear color-magnitude relation is found to be around 0.08 mag for the subsample of SNe with (B_max_-V_max_)<=0.05 mag and around 0.11 mag for the subsample with (B_max_-V_max_)<=0.2 mag. This small dispersion is consistent with being mostly due to observational errors. The method presented here and the conventional light-curve fitting methods can be combined to further improve statistical dispersions of distance estimates. It can be combined with the magnitude at maximum to deduce dust extinction. The slopes of the color-magnitude relation may also be used to identify intrinsically different SN Ia systems. The method provides a tool that is fundamental to using SNe Ia to estimate cosmological parameters such as the Hubble constant and the mass and dark energy content of the universe. Keywords: Cosmology: Cosmological Parameters, Cosmology: Distance Scale, Stars: Supernovae: General
Retrieve 96 NED objects in this reference.
Please click here for ADS abstract

Back to NED Home