Understanding U-band Spectroscopic Variations in Type Ia Supernovae
Abstract
The Nearby Supernova Factory obtains spectrophotometric time series of Type Ia supernovae (SNe Ia). Observations include the so far poorly explored U band region, where we find significant flux variations best explained by different explosion scenarios (rather than e.g. metallicity changes). We show this using SYNAPPS fits of well measured SNe as well as non-parametric clustering algorithms applied to a larger sample of SNe. Both imply significant differences between narrow and wide lightcurve "normal" SNe Ia. The same data also allow us to map High Velocity features in the Ca H&K region, and we discuss how these relate to measurements of SN Ia lightcurve colors. We summarize potential effects on supernova cosmology based on these findings.
- Publication:
-
American Astronomical Society Meeting Abstracts #223
- Pub Date:
- January 2014
- Bibcode:
- 2014AAS...22335419N