Early-time observations of Type Ia supernovae to reveal progenitors and metallicity
Abstract
SNe Ia remain nature's best standardized candles, and yet their progenitors have long been a mystery. However, it is now clear that there is a multiplicity of SN Ia progenitors. Recent findings that SNe Ia correct to different absolute magnitudes in different mass galaxies may be related to differing progenitors, and/or progenitor metallicity. With this proposal we will obtrain early GMOS spectroscopy of SNe a few days after explosion with three main goals: (1) to trigger our proposed HST Cycle 20 STIS observations probing early UV spectra and thus metallicity, (2) trigger our high resolution spectroscopy time on Keck HIRES and VLT X-shooter to search for circumstellar material indicative of a single degenerate origin, (3) build the first well-controlled sample studying unburned progenitor carbon in SNe Ia, testing whether this traces white dwarf mergers or explosion physics. Our results depend on early-time observations for which the queue-scheduled Gemini is uniquely suited.
- Publication:
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NOAO Proposal
- Pub Date:
- August 2012
- Bibcode:
- 2012noao.prop..491H