Discovery of the Fastest Early Optical Emission from Overluminous SN Ia 2020hvf: A Thermonuclear Explosion within a Dense Circumstellar Environment

  title={Discovery of the Fastest Early Optical Emission from Overluminous SN Ia 2020hvf: A Thermonuclear Explosion within a Dense Circumstellar Environment},
  author={Jiachen Jiang and Keiichi Maeda and Miho Kawabata and Mamoru Doi and Toshikazu Shigeyama and Masaomi Tanaka and Nozomu Tominaga and Ken’ichi Nomoto and Yuu Niino and Shigeyuki Sako and Ryou Ohsawa and Malte Schramm and Masayuki Yamanaka and Naoto Kobayashi and Hidenori Takahashi and Tatsuya Nakaoka and Koji S. Kawabata and Keisuke Isogai and Tsutomu Aoki and Sohei Kondo and Y. A. Mori and Ko Arimatsu and Toshihiro Kasuga and Shin-ichiro Okumura and Seitaro Urakawa and Daniel E. Reichart and Kenta Taguchi and Noriaki Arima and Jin Beniyama and Kohki Uno and Taisei Hamada},
  journal={The Astrophysical Journal Letters},
In this Letter we report a discovery of a prominent flash of a peculiar overluminous Type Ia supernova, SN 2020hvf, in about 5 hr of the supernova explosion by the first wide-field mosaic CMOS sensor imager, the Tomo-e Gozen Camera. The fast evolution of the early flash was captured by intensive intranight observations via the Tomo-e Gozen high-cadence survey. Numerical simulations show that such a prominent and fast early emission is most likely generated from an interaction between 0.01 M… 

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