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Title: The Effects of r-Process Enrichment in Hydrogen-rich Supernovae

Core-collapse supernovae (SNe) are candidate sites for rapid neutron capture process (r-process) nucleosynthesis. We explore the effects of enrichment fromr-process nuclei on the light curves of hydrogen-rich SNe and assess the detectability of these signatures. We modify the radiation hydrodynamics code, SuperNova Explosion Code, to include the approximate effects of opacity and radioactive heating fromr-process elements in the supernova (SN) ejecta. We present models spanning a range of totalr-process massesMrand their assumed radial distribution within the ejecta, finding thatMr≳ 10−2Mis sufficient to induce appreciable differences in their light curves as compared to ordinary hydrogen-rich SNe (without anyr-process elements). The primary photometric signatures ofr-process enrichment include a shortening of the plateau phase, coinciding with the hydrogen-recombination photosphere retreating to ther-process-enriched layers, and a steeper post-plateau decline associated with a reddening of the SN colors. We compare ourr-process-enriched models to ordinary SNe models and observational data, showing that yields ofMr≳ 10−2Mare potentially detectable across several of the metrics used by transient observers, provided thatr-process-rich layers are mixed at least halfway to the ejecta surface. This detectability threshold can roughly be reproduced analytically using a two-zone (kilonova-within-an-SN) picture. Assuming that a small fraction of SNe produce a detectabler-process yield ofMr≳ 10−2M, and respecting constraints on the total Galactic production rate, we estimate that ≳103–104SNe need be observed to find oner-enriched event, a feat that may become possible with the Vera Rubin Observatory.

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Author(s) / Creator(s):
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Publisher / Repository:
DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astrophysical Journal
Medium: X Size: Article No. 212
["Article No. 212"]
Sponsoring Org:
National Science Foundation
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