SN 2017gmr: An Energetic Type II-P Supernova with Asymmetries

Jennifer E. Andrews, D. J. Sand, S. Valenti, Nathan Smith, Raya Dastidar, D. K. Sahu, Kuntal Misra, Avinash Singh, D. Hiramatsu, P. J. Brown, G. Hosseinzadeh, S. Chen, L. Chomiuk, A. Cikota, E. Congiu, B. Cseh, Scott Davis, N. Elias-Rosa, T. Faran, Morgan FraserL. Galbany, C. Gall, A. Gal-Yam, Anjasha Gangopadhyay, M. Gromadzki, C. Inserra, E. Kankare, H. Kuncarayakti, V. Kouprianov, Pankaj Sanwal, K. Sarneczky, M. Shahbandeh, Mridweeka Singh, S. Smartt, J. Strader, M. D. Stritzinger, J. C. Wheeler, Danfeng Xiang, O. Yaron, D. R. Young, Junbo Zhang

9 Citations (Scopus)

Abstract

We present high-cadence UV, optical, and near-infrared data on the luminous Type II-P supernova SN 2017gmr from hours after discovery through the first 180 days. SN 2017gmr does not show signs of narrow, high-ionization emission lines in the early optical spectra, yet the optical light-curve evolution suggests that an extra energy source from circumstellar medium (CSM) interaction must be present for at least 2 days after explosion. Modeling of the early light curve indicates a ∼500 R o progenitor radius, consistent with a rather compact red supergiant, and late-time luminosities indicate that up to 0.130 ± 0.026 M o of 56Ni are present, if the light curve is solely powered by radioactive decay, although the 56Ni mass may be lower if CSM interaction contributes to the post-plateau luminosity. Prominent multipeaked emission lines of Hα and [O i] emerge after day 154, as a result of either an asymmetric explosion or asymmetries in the CSM. The lack of narrow lines within the first 2 days of explosion in the likely presence of CSM interaction may be an example of close, dense, asymmetric CSM that is quickly enveloped by the spherical supernova ejecta.

Original languageEnglish
Article number43
JournalAstrophysical Journal
Volume885
Issue number1
Number of pages23
ISSN0004-637X
DOIs
Publication statusPublished - 1 Nov 2019

Keywords

  • Type II supernovae
  • Core-collapse supernovae
  • Massive stars

Fingerprint

Dive into the research topics of 'SN 2017gmr: An Energetic Type II-P Supernova with Asymmetries'. Together they form a unique fingerprint.

Cite this