Abstract
We report the first detection of a credible progenitor system for a Type Ic supernova (SN Ic), SN 2017ein. We present spectra and photometry of the SN, finding it to be similar to carbon-rich, low-luminosity SNe Ic. Using a post-explosion Keck adaptive optics image, we precisely determine the position of SN 2017ein in pre-explosion HST images, finding a single source coincident with the SN position. This source is marginally extended, and is consistent with being a stellar cluster. However, under the assumption that the emission of this source is dominated by a single point source, we perform point-spread function photometry, and correcting for line-of-sight reddening, we find it to have MF555W = -7.5 ± 0.2 mag and mF555W - mF814W = -0.67 ± 0.14 mag. This source is bluer than the main sequence and brighter than almost all Wolf-Rayet stars, however, it is similar to some WC+O- and B-star binary systems. Under the assumption that the source is dominated by a single star, we find that it had an initial mass of 55-15+20M⊙. We also examined binary star models to look for systems that match the overall photometry of the pre-explosion source and found that the best-fitting model is an 80+48M⊙ close binary system in which the 80M⊙ star is stripped and explodes as a lower mass star. Late-time photometry after the SN has faded will be necessary to cleanly separate the progenitor star emission from the additional coincident emission.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 2072-2084 |
| Number of pages | 13 |
| Journal | Monthly Notices of the Royal Astronomical Society |
| Volume | 480 |
| Issue number | 2 |
| DOIs | |
| State | Published - Oct 2018 |
Funding
The UCSC group is supported in part by NSF grant AST– 1518052, the Gordon & Betty Moore Foundation, the Heising– Simons Foundation, and by fellowships from the Alfred P. Sloan Foundation and the David and Lucile Packard Foundation to RJF. University of Hawaii, the Pan-STARRS Project Office, the Max-Planck Society and its participating institutes, the Max Planck Institute for Astronomy, Heidelberg and the Max Planck Institute for Extraterrestrial Physics, Garching, The Johns Hopkins University, Durham University, the University of Edinburgh, the Queen’s University Belfast, the Harvard-Smithsonian Center for Astrophysics, the Las Cumbres Observatory Global Telescope Network Incorporated, the National Central University of Taiwan, the Space Telescope Science Institute, the National Aeronautics and Space Administration under Grant No. NNX08AR22G issued through the Planetary Science Division of the NASA Science Mission Directorate, the National Science Foundation grant no. AST-1238877, the University of Maryland, Eotvos Lorand University (ELTE), the Los Alamos National Laboratory, and the Gordon and Betty Moore Foundation. We thank Raj Chowdhury and Bella Nguyen for help with Nickel observations. We also thank David Coulter, César Rojas-Bravo, and Matthew Siebert for help with Shane and Mayall observations. The UCSC group is supported in part by NSF grant AST-1518052, the Gordon & Betty Moore Foundation, the Heising-Simons Foundation, and by fellowships from the Alfred P. Sloan Foundation and the David and Lucile Packard Foundation to RJF. Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and NASA. The observatory was made possible by the generous financial support of theW. M. Keck Foundation. We wish to recognise and acknowledge the cultural significance that the summit of Mauna Kea has within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain. Some of the data in this publication were calibrated using object catalogues from the Pan-STARRS1 Surveys. The Pan-STARRS1 Surveys (PS1) and the PS1 public science archive have been made possible through contributions by the Institute for Astronomy, the University of Hawaii, the Pan-STARRS Project Office, the Max-Planck Society and its participating institutes, the Max Planck Institute for Astronomy, Heidelberg and the Max Planck Institute for Extraterrestrial Physics, Garching, The Johns Hopkins University, Durham University, the University of Edinburgh, the Queen's University Belfast, the Harvard-Smithsonian Center for Astrophysics, the Las Cumbres Observatory Global Telescope Network Incorporated, the National Central University of Taiwan, the Space Telescope Science Institute, the National Aeronautics and Space Administration under Grant No. NNX08AR22G issued through the Planetary Science Division of the NASA Science Mission Directorate, the National Science Foundation grant no. AST-1238877, the University of Maryland, Eotvos Lorand University (ELTE), the Los Alamos National Laboratory, and the Gordon and Betty Moore Foundation. The Hubble Space Telescope (HST) is operated by NASA/ESA. The HST data used in this manuscript come from programme GO-10877 (PI Li). Some of our analysis is based on data obtained from the HST archive operated by STScI. We acknowledge the use of public data from the Swift data archive. Some of the data presented in this manuscript come from the Kitt Peak National Observatory (KPNO) 4-m telescope through programme 2017A-0306 (PI Foley). KPNO is operated by the Association of Universities for Research in Astronomy, Inc. (AURA) under cooperative agreement with the National Science Foundation. The Nickel and Shane telescopes are operated by the University of California and Lick Observatories. Some of the data presented in this manuscript come from UCO/Lick programmes 2017Q2-N007, 2017Q3-N005 (PI Kilpatrick) and 2017A-S011, 2017B-S018 (PI Foley). This work makes use of observations performed by the Las Cumbres Global Telescope Network through programme 2017AB-012 (PI Kilpatrick).
Keywords
- Stars: evolution
- Supernovae: general
- Supernovae: individual (SN 2017ein)
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Space and Planetary Science