Dissecting the Energetics of Supernovae at High Spectral Resolution: LEM Studies of Supernovae and Supernova Remnants

Supernovae chemically enrich their environments, drive future generations of star formation, and can accelerate particles up to the knee of the cosmic-ray spectrum. Supernovae are inherently asymmetric processes, and the degree of asymmetry is determined by the explosion and the internal structure of the progenitor star. Detailed studies of supernovae and their remnants can provide clues to the explosion physics and progenitor evolution by: (1) detecting trace elements which are formed via asymmetric neutrino emission during the explosion; (2): measuring bulk asymmetries in the velocity of differing layers of ejecta; and (3): probing the mass loss properties of the progenitor. High spectral resolution optical and NIR studies of supernovae and their remnants partially address these questions, providing important diagnostics which allow for a reconstruction of the dynamics of the highest density ejecta. However, in most cases, ejecta in supernova remnants (and some supernovae) are brightest in X-rays. CCD resolution studies of supernova remnants can provide insight into the bulk properties of supernovae, but CCDs lack the resolution to detect emission from trace elements and, importantly, are generally unable to measure bulk velocities of the ejecta. The Line Emission Mapper is a proposed NASA probe class misssion which will map the properties of supernovae and their remnants in high spectral resolution. Two eV microcalorimeter resolution will enable the reconstruction of explosion physics in both core-collapse and Type Ia supernova remnants in our Galaxy and the local group. The high spectral resolution will measure bulk ejecta velocities, as well as detect trace elements which can provide clues as to the explosion mechanism. LEM will allow for tomographic reconstruction of supernova remnants, probing the dynamics of ejecta and relating them back to supernova explosion models. We present specific examples of LEM observations of Galactic and extragalactic supernova remnants, and discuss how these studies with LEM will address the role of supernovae in chemical enrichment and feedback within their ecosystems.