Targeting two 2-year old Type IIn supernovae with Chandra

Abstract

Type IIn supernovae (SNe IIn) are a heterogeneous class of supernovae (SNe) believed to be powered by vigorous circumstellar (CS) interaction. Their evolutionary status remains an open question. X-rays are the product of CS interaction and hence offer unique constraints on the shock energetics and CS medium characteristics. X-rays are a direct probe of the column density and abundances, and therefore also of the total mass loss of the progenitor star during the last phases before explosion. In SNe IIn late time optical and IR emission is also powered by the CS interaction, providing a good indicator for the X-ray brightness. In this proposal we request 80 ks of Chandra ACIS time to observe optically bright (m_v~14) SNe IIn SN 2017hcc and 2017gas.