S21A0014

Early high-resolution spectroscopy is essential for understanding of progenitors of supernovae (SNe). Time-variable circumstellar (CS) signatures can be used to map the final stages of the progenitor star through its mass loss history. As the expected line widths are less than 100 km/s, high-resolution spectra are needed. Thanks to recent high-cadence surveys, very early follow-up can be made to explore CS material in a new time domain than previously possible. Here we propose a pilot study to focus one nearby core-collapse SN in a time sequence begging within a week after the explosion. Additional few SNe will be observed in time sequence including the early rising phase, which already expands our time domain in high resolution spectra even without the data in the first week. The new data will expand the study of the CS environment so far obtained only for extreme cases as the tip of the iceberg to a generic picture covering various progenitors.

This document was translated from L^AT_EX by H^EV^EA.