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arXiv · 1910.11343

An optical search for transients lasting a few seconds

Michael W. Richmond·Masaomi Tanaka·Tomoki Morokuma·Shigeyuki Sako·Ryou Ohsawa·Noriaki Arima·Nozomu Tominaga·Mamoru Doi·Tsutomu Aoki·Ko Arimatsu·Makoto Ichiki·Shiro Ikeda·Yoshifusa Ita·Toshihiro Kasuga·Koji S. Kawabata·Hideyo Kawakita·Naoto Kobayashi·Mitsuru Kokubo·Masahiro Konishi·Hiroyuki Maehara·Hiroyuki Mito·Takashi Miyata·Yuki Mori·Mikio Morii·Kentaro Motohara·Yoshikazu Nakada·Shin-Ich·Hiroki Onozato·Yuki Sarugaku·Mikiya Sato·Toshikazu Shigeyama·Takao Soyano·Hidenori Takahashi·Ataru Tanikawa·Ken'ichi Tarusawa·Seitaro Urakawa·Fumihiko Usui·Junichi Watanabe·Takuya Yamashita·Makoto Yoshikawa
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Abstract

Using a prototype of the Tomo-e Gozen wide-field CMOS mosaic camera, we acquire wide-field optical images at a cadence of 2 Hz and search them for transient sources of duration 1.5 to 11.5 seconds. Over the course of eight nights, our survey encompasses the equivalent of roughly two days on one square degree, to a fluence equivalent to a limiting magnitude about $V = 15.6$ in a 1-second exposure. After examining by eye the candidates identified by a software pipeline, we find no sources which meet all our criteria. We compute upper limits to the rate of optical transients consistent with our survey, and compare those to the rates expected and observed for representative sources of ephemeral optical light.

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Michael W. Richmond, Masaomi Tanaka, Tomoki Morokuma, Shigeyuki Sako, Ryou Ohsawa, Noriaki Arima, Nozomu Tominaga, Mamoru Doi, Tsutomu Aoki, Ko Arimatsu, Makoto Ichiki, Shiro Ikeda, Yoshifusa Ita, Toshihiro Kasuga, Koji S. Kawabata, Hideyo Kawakita, Naoto Kobayashi, Mitsuru Kokubo, Masahiro Konishi, Hiroyuki Maehara, Hiroyuki Mito, Takashi Miyata, Yuki Mori, Mikio Morii, Kentaro Motohara, Yoshikazu Nakada, Shin-Ich, Hiroki Onozato, Yuki Sarugaku, Mikiya Sato, Toshikazu Shigeyama, Takao Soyano, Hidenori Takahashi, Ataru Tanikawa, Ken'ichi Tarusawa, Seitaro Urakawa, Fumihiko Usui, Junichi Watanabe, Takuya Yamashita, Makoto Yoshikawa. 2019-10-24. An optical search for transients lasting a few seconds. https://doi.org/10.1093/pasj%2Fpsz120

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