# # Program information file # PROGRAM_ID 2024B069 PROGRAM_TITLE The Infrared Lives of Supernovae: Spectral Time Series Observations with IRTF PROGRAM_INV1 Willem Hoogendam PROGRAM_INV2 Benjamin Shappee PROGRAM_INV3 David Jones PROGRAM_INV4 Katie Auchettl PROGRAM_INV5 Jennifer Shi PROGRAM_SCICAT extra-galactic PROGRAM_ABSTRACT_BEG We request three nights of classical observations to acquire NIR spectral time series data of Type Ia supernovae [SNe Ia] using the SpeX instrument. We will use these data to measure the amount of unburnt carbon, estimate the completion time of nuclear burning, and constrain the presence of any potential hydrogen or helium, as well as explore differences in the early NIR spectra of peculiar SNe Ia. With these measurements, we will differentiate between various progenitor scenarios for our SNe Ia sample, specifically between the sub-Chandrasekhar mass versus Chandrasekhar mass and companion versus no companion scenarios. Objects will be pre-peak SNe Ia discovered by public all-sky surveys. Currently, there are few NIR time series data with pre-peak, peak, and post-peak observations. These NIR spectral time series will provide important new data of SNe Ia. PROGRAM_ABSTRACT_END