Colloquium on Apr. 23, 2020

Rapid follow-up observations of young Type Ia supernovae in the nearby galaxy

Speaker: Miho Kawabata  (Kyoto University)

Venue: Video Conference

Time: 3:00 PM, Thursday, Apr. 23, 2020

Abstract: 

There is a well-established correlation between the peak luminosity and the light-curve decline rate, which is known as the luminosity-width relation (Phillips 1993). This relation allows SNe Ia to be used as precise standardized candles to measure the cosmic-scale distances to remote galaxies and thus the cosmological parameters (Riess et al. 1998; Perlmutter et al. 1999). However, there are still under debate about the progenitor system of SNe Ia. Some methods to distinguish the progenitor scenario are suggesting. For example, in the single degenerate scenario, some previous studies suggest the interaction between the ejecta of SN and companion can be seen within a few days from the explosion (e.g. Kasen, 2010). When the ejecta collide with the companion, it creates a shock cooling signature over the first few days. The signature depends on the size, distance of the companion and the viewing angle. From the data at few days after the explosion. I perform the rapid follow-up observations using the 1.5m Kanata telescope at Higashi-Hiroshima Observatory, and 3.8m Seimei telescope at Okayama Observatory. In this talk, I introduce the optical and NIR follow-up observational strategy and good sample from which data was obtained within a few days from the explosion (details for Kawabata et al. 2020).