@article{612e63aa0b094fbaab2c1046dcf5c47a,
title = "Ultraviolet Detection of the Binary Companion to the Type IIb SN 2001ig",
abstract = "We present HST/WFC3 ultraviolet imaging in the F275W and F336W bands of the Type IIb SN 2001ig at an age of more than 14 years. A clear point source is detected at the site of the explosion, with m F275W = 25.39 ±0.10 and m F336W = 25.88 ±0.13 mag. Despite weak constraints on both the distance to the host galaxy NGC 7424 and the line-of-sight reddening to the supernova, this source matches the characteristics of an early B-type main-sequence star with 19,000 < T eff < 22,000 K and log(Lbol L⊙). A BPASS v2.1 binary evolution model, with primary and secondary masses of 13 M o and 9 M o, respectively, is found to simultaneously resemble, in the Hertzsprung-Russell diagram, both the observed location of this surviving companion, and the primary star evolutionary endpoints for other Type IIb supernovae. This same model exhibits highly variable late-stage mass loss, as expected from the behavior of the radio light curves. A Gemini/GMOS optical spectrum at an age of 6 years reveals a narrow He ii λ4686 emission line, indicative of continuing interaction with a dense circumstellar medium at large radii from the progenitor. We review our findings on SN 2001ig in the context of binary evolution channels for stripped-envelope supernovae. Owing to the uncrowded nature of its environment in the ultraviolet, this study of SN 2001ig represents one of the cleanest detections to date of a surviving binary companion to a Type IIb supernova.",
keywords = "binaries: close, binaries: general, stars: evolution, stars: massive, supernovae: general, supernovae: individual (SN 2001ig)",
author = "Ryder, {Stuart D.} and Dyk, {Schuyler D.Van} and Fox, {Ori D.} and Emmanouil Zapartas and Mink, {Selma E.De} and Nathan Smith and Emily Brunsden and Bostroem, {K. Azalee} and Filippenko, {Alexei V.} and Isaac Shivvers and Weikang Zheng",
note = "Funding Information: This work is based in part on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute (STScI), which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. Support was provided by NASA through grants GO-14075 and AR-14295 from STScI. It is also based in part on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), Ministerio de Ciencia, Tecnolog{\'i}a e Innovaci{\'o}n Productiva (Argentina), and Minist{\'e}rio da Ci{\^e}ncia, Tecnologia e Inova{\c c}{\~a}o (Brazil). We thank the referee for their suggestions, and are grateful to J. J.Eldridge for discussions regarding the BPASS models. A.V.F.{\textquoteright}s group is also grateful for generous financial assistance from the Christopher R. Redlich Fund, the TABASGO Foundation, NSF grant AST-1211916, and the Miller Institute for Basic Research in Science (U.C. Berkeley). E.Z. is supported by a grant of the Netherlands Research School for Astronomy (NOVA). S.d.M. acknowledges support by a Marie Sklodowska-Curie Action (H2020 MSCA-IF-2014, project BinCosmos, id 661502). Publisher Copyright: {\textcopyright} 2018. The American Astronomical Society. All rights reserved..",
year = "2018",
month = mar,
day = "20",
doi = "10.3847/1538-4357/aaaf1e",
language = "English (US)",
volume = "856",
journal = "Astrophysical Journal",
issn = "0004-637X",
publisher = "IOP Publishing Ltd.",
number = "1",
}