We present JWST spectral and photometric observations of the Type IIP supernova (SN) 2022acko at ~50 days past explosion. These data are the first JWST spectral observations of a core-collapse SN. We identify ~30 different H I features, other features associated with products produced from the CNO cycle, and s-process elements such as Sc II and Ba II. By combining the JWST spectra with ground-based optical and NIR spectra, we construct a full Spectral Energy Distribution from 0.4 to 25 microns and find that the JWST spectra are fully consistent with the simultaneous JWST photometry. The data lack signatures of CO formation and we estimate a limit on the CO mass of < 10^{-8} solar mass. We demonstrate how the CO fundamental band limits can be used to probe underlying physics during stellar evolution, explosion, and the environment. The observations indicate little mixing between the H envelope and C/O core in the ejecta and show no evidence of dust. The data presented here set a critical baseline for future JWST observations, where possible molecular and dust formation may be seen.
@article{arxiv.2401.14474,
title = {JWST NIRSpec+MIRI Observations of the nearby Type IIP supernova 2022acko},
author = {M. Shahbandeh and C. Ashall and P. Hoeflich and E. Baron and O. Fox and T. Mera and J. DerKacy and M. D. Stritzinger and B. Shappee and D. Law and J. Morrison and T. Pauly and J. Pierel and K. Medler and J. Andrews and D. Baade and A. Bostroem and P. Brown and C. Burns and A. Burrow and A. Cikota and D. Cross and S. Davis and T. de Jaeger and A. Do and Y. Dong and E. Hsiao and I. Dominguez and L. Galbany and D. Janzen and J. Jencson and E. Hoang and E. Karamehmetoglu and B. Khaghani and K. Krisciunas and S. Kumar and J. Lu and P. Mazzali and N. Morrell and F. Patat and J. Pearson and C. Pfeffer and L. Wang and Y. Yang and Y. Z. Cai and Y. Camacho-Neves and N. Elias-Rosa and M. Lundquist and J. Maund and M. Phillips and A. Rest and N. Retamal and S. Stangl and M. Shrestha and C. Stevens and N. Suntzeff and C. Telesco and M. Tucker and R. Foley and S. Jha and L. Kwok and C. Larison and N. LeBaron and S. Moran and J. Rho and I. Salmaso and J. Schmidt and S. Tinyanont},
journal= {arXiv preprint arXiv:2401.14474},
year = {2024}
}