The electron-capture origin of supernova 2018zd Daichi Hiramatsu1;2∗, D. Andrew Howell1;2, Schuyler D. Van Dyk3, Jared A. Goldberg2, Keiichi Maeda4;5, Takashi J. Moriya6;7, Nozomu Tominaga8;5, Ken’ichi Nomoto5, Griffin Hosseinzadeh9, Iair Arcavi10;11, Curtis McCully1;2, Jamison Burke1;2, K. Azalee Bostroem12, Stefano Valenti12, Yize Dong12, Peter J. Brown13, Jennifer E. Andrews14, Christopher Bilinski14, G. Grant Williams14;15, Paul S. Smith14, Nathan Smith14, David J. Sand14, Gagandeep S. Anand16;17, Chengyuan Xu18, Alexei V.Filippenko19;20, Melina C. Bersten21;22;5, Gaston´ Folatelli21;22;5, Patrick L. Kelly23, Toshi- hide Noguchi24 & Koichi Itagaki25 *Corresponding author. Email:
[email protected] 1Las Cumbres Observatory, 6740 Cortona Drive, Suite 102, Goleta, CA 93117-5575, USA 2Department of Physics, University of California, Santa Barbara, CA 93106-9530, USA 3Caltech/Spitzer Science Center, Caltech/IPAC, Mailcode 100-22, Pasadena, CA 91125, USA 4Department of Astronomy, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606- 8502, Japan 5Kavli Institute for the Physics and Mathematics of the Universe (WPI), The University of Tokyo Institutes for Advanced Study, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277- 8583, Japan arXiv:2011.02176v1 [astro-ph.HE] 4 Nov 2020 6National Astronomical Observatory of Japan, National Institutes of Natural Sciences, 2-21-1 Os- awa, Mitaka, Tokyo 181-8588, Japan 7School of Physics and Astronomy, Faculty of Science, Monash University, Clayton, Victoria 1 3800, Australia