A growing number of core-collapse supernovae (SNe) that show evidence for interaction with dense circumstellar medium (CSM) are accompanied by “precursor” optical emission rising weeks to months prior to the explosion. The precursor luminosities greatly exceed the Eddington limit of the progenitor star, implying that they are accompanied by substantial mass loss. Here, we present a semi-analytic model for SN precursor light curves, which we apply to constrain the properties and mechanisms of the pre-explosion mass loss. We explore two limiting mass-loss scenarios: (1) an “eruption” arising from shock breakout following impulsive energy deposition below the stellar surface; and (2) a steady “wind,” due to sustained heating of the progenitor envelope. The eruption model, which resembles a scaled-down version of Type IIP SNe, can explain the luminosities and timescales of well-sampled precursors, for ejecta masses ∼ 0.1–1
This content will become publicly available on May 1, 2023
- Publication Date:
- NSF-PAR ID:
- 10351657
- Journal Name:
- The Astrophysical Journal
- Volume:
- 930
- Issue:
- 2
- Page Range or eLocation-ID:
- 150
- ISSN:
- 0004-637X
- Sponsoring Org:
- National Science Foundation
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