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Arxiv: Discovery of a Relativistic Stripped Envelope Type Ic-BL Supernova at z = 2.83 with JWST Published: 6/7/2024 7:47:45 PM Updated: 10/1/2024 5:55:14 PM

Paper abstract: We present JWST NIRCam and NIRSpec observations of a Type Ic supernova (SNIc) and its host galaxy (JADES-GS+53.13533-27.81457) at z = 2.83. This SN(named SN 2023adta) was identified in deep James Webb Space Telescope(JWST)/NIRCam imaging from the JWST Advanced Deep Extragalactic Survey (JADES)Program. Follow-up observations with JWST/NIRSpec provided a spectroscopicredshift of z = 2.83 and the classification as a SN Ic-BL. The light curve ofSN 2023adta matches well with other stripped envelope supernovae and we find ahigh peak luminosity, M_V = -19.0 \pm 0.2 mag, based on the distribution ofbest-fit SNe. The broad absorption features in its spectrum are consistent withother SNe Ic-BL 1-3 weeks after peak brightness. We measure a Ca II NIR tripletexpansion velocity of 29{,}000 \pm 2{,}000 km s^{-1}. The host galaxy of SN2023adta is irregular, and modeling of its spectral energy distribution (SED)indicates a metallicity of Z = 0.35^{+0.16}_{-0.08} Z_{\odot}. Thisenvironment is consistent with the population of low-z SNe Ic-BL which preferlower metallicities relative to other stripped envelope supernovae, and tracklong duration \gamma-ray burst (LGRB) environments. We do not identify anyGRBs that are coincident with SN 2023adta. Given the rarity of SNe Ic-BL in thelocal universe, the detection of a SN Ic-BL at z = 2.83 could indicate thattheir rates are enhanced at high redshift.