Description
A sample of 109 Type Ia supernovae (SNe Ia) with recession velocity <~30000km/s is compiled from published SN Ia light curves to explore the expansion rate of the local universe. Based on the color parameter {Delta}C_12_ and the decline rate {delta}m15, we found that the average absorption-to-reddening ratios for SN Ia host galaxies are R_UBVI_=4.37+/-0.25, 3.33+/-0.11, 2.30+/-0.11, and 1.18+/-0.11, which are systematically lower than the standard values in the Galaxy. We investigated the correlations of the intrinsic luminosity with light-curve decline rate, color index, and SN environmental parameters.
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