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arXiv · 2101.02454

Detectability of optical transients with timescales of sub-seconds

Ko Arimatsu·Kohji Tsumura·Fumihiko Usui·Takafumi Ootsubo·Jun-ichi Watanabe
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Abstract

We search for optical transient sources with durations of $\sim 0.1$ to $\sim 1.3$ s using a dataset obtained in the Organized Autotelescopes for Serendipitous Event Survey (OASES) observation campaign. Since the OASES observations were carried out using two independent wide-field and high-cadence observation systems monitored the same field simultaneously, the obtained dataset provides a unique opportunity to develop a robust detection method for sub-second optical transients. In the dataset of a selected field around the ecliptic and the Galactic plane, we find no astronomical event candidate that satisfies our detection criteria. From the non-detection result, we derive an upper limit on the event rate of sub-second transients around the ecliptic and the Galactic plane for the first time, obtaining $\sim 0.090$ and $\sim 0.38~{\rm hr^{-1}~deg^{-2}}$ for $m = 12$ and 13 Vmag, respectively. In addition, future prospects of the sub-second scale transient event surveys are discussed.

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Ko Arimatsu, Kohji Tsumura, Fumihiko Usui, Takafumi Ootsubo, Jun-ichi Watanabe. 2021-01-07. Detectability of optical transients with timescales of sub-seconds. https://doi.org/10.3847/1538-3881/abd94d

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