Early-type Host Galaxies of Type Ia Supernovae. II. Evidence for Luminosity Evolution in Supernova Cosmology

Understand

The most direct and strongest evidence for the presence of dark energy is provided by the measurement of galaxy distances using SNe Ia.

• This result is based on the assumption that the corrected brightness of SN Ia through the empirical standardization would not evolve with look-back time.
• Recent studies have shown, however, that the standardized brightness of SN Ia is correlated with host morphology, host mass, and local star formation rate (SFR), suggesting a possible correlation with stellar population property.
• To understand the origin of these correlations, we have continued our spectroscopic observations to cover most of the reported nearby early-type host galaxies.