SN 2017gmr: An Energetic Type II-P Supernova with Asymmetries
- Author(s): Andrews, Jennifer E
- Sand, DJ
- Valenti, S
- Smith, Nathan
- Dastidar, Raya
- Sahu, DK
- Misra, Kuntal
- Singh, Avinash
- Hiramatsu, D
- Brown, PJ
- Hosseinzadeh, G
- Wyatt, S
- Vinko, J
- Anupama, GC
- Arcavi, I
- Ashall, Chris
- Benetti, S
- Berton, Marco
- Bostroem, KA
- Bulla, M
- Burke, J
- Chen, S
- Chomiuk, L
- Cikota, A
- Congiu, E
- Cseh, B
- Davis, Scott
- Elias-Rosa, N
- Faran, T
- Fraser, Morgan
- Galbany, L
- Gall, C
- Gal-Yam, A
- Gangopadhyay, Anjasha
- Gromadzki, M
- Haislip, J
- Howell, DA
- Hsiao, EY
- Inserra, C
- Kankare, E
- Kuncarayakti, H
- Kouprianov, V
- Kumar, Brajesh
- Li, Xue
- Lin, Han
- Maguire, K
- Mazzali, P
- McCully, C
- Milne, P
- Mo, Jun
- Morrell, N
- Nicholl, M
- Ochner, P
- Olivares, F
- Pastorello, A
- Patat, F
- Phillips, M
- Pignata, G
- Prentice, S
- Reguitti, A
- Reichart, DE
- Rodriguez, O
- Rui, Liming
- Sanwal, Pankaj
- Sarneczky, K
- Shahbandeh, M
- Singh, Mridweeka
- Smartt, S
- Strader, J
- Stritzinger, MD
- Szakats, R
- Tartaglia, L
- Wang, Huijuan
- Wang, Lingzhi
- Wang, Xiaofeng
- Wheeler, JC
- Xiang, Danfeng
- Yaron, O
- Young, DR
- Zhang, Junbo
- et al.
Published Web Location
https://doi.org/10.3847/1538-4357/ab43e3Abstract
© 2019. The American Astronomical Society. All rights reserved. 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.