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Title: Circumstellar Medium Interaction in SN 2018lab, A Low-luminosity Type IIP Supernova Observed with TESS
Abstract

We present photometric and spectroscopic data of SN 2018lab, a low-luminosity Type IIP supernova (LLSN) with aV-band peak luminosity of −15.1 ± 0.1 mag. SN 2018lab was discovered by the Distance Less Than 40 Mpc (DLT40) SN survey only 0.73 days post-explosion, as determined by observations from the Transiting Exoplanet Survey Satellite (TESS). TESS observations of SN 2018lab yield a densely sampled, fast-rising, early-time light curve likely powered by ejecta–circumstellar medium (CSM) interaction. The blueshifted, broadened flash feature in the earliest spectra (<2 days) of SN 2018lab provides further evidence for ejecta–CSM interaction. The early emission features in the spectra of SN 2018lab are well described by models of a red supergiant progenitor with an extended envelope and a close-in CSM. As one of the few LLSNe with observed flash features, SN 2018lab highlights the need for more early spectra to explain the diversity of the flash feature morphology of Type II SNe.

 
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Award ID(s):
1813466 2008108
NSF-PAR ID:
10401464
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more » ; ; ; ; « less
Publisher / Repository:
DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
945
Issue:
2
ISSN:
0004-637X
Format(s):
Medium: X Size: Article No. 107
Size(s):
["Article No. 107"]
Sponsoring Org:
National Science Foundation
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