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arXiv · 1210.6909

Unusual Long and Luminous Optical Transient in the Subaru Deep Field

Yuji Urata·Patrick P. Tsai·Kuiyun Huang·Tomoki Morokuma·Naoki Yasuda·Masaomi Tanaka·Kentaro Motohara·Masao Hayashi·Nobunari Kashikawa·Chun Ly·Matthew A. Malkan
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Abstract

We present observations of SDF-05M05, an unusual optical transient discovered in the Subaru Deep Field (SDF). The duration of the transient is > ~800 d in the observer frame, and the maximum brightness during observation reached approximately 23 mag in the i' and z' bands. The faint host galaxy is clearly identified in all 5 optical bands of the deep SDF images. The photometric redshift of the host yields z~0.6 and the corresponding absolute magnitude at maximum is ~-20. This implies that this event shone with an absolute magnitude brighter than -19 mag for approximately 300 d in the rest frame, which is significantly longer than a typical supernova and ultra-luminous supernova. The total radiated energy during our observation was 1x10^51 erg. The light curves and color evolution are marginally consistent with some of luminous IIn supernova. We suggest that the transient may be a unique and peculiar supernova at intermediate redshift.

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Yuji Urata, Patrick P. Tsai, Kuiyun Huang, Tomoki Morokuma, Naoki Yasuda, Masaomi Tanaka, Kentaro Motohara, Masao Hayashi, Nobunari Kashikawa, Chun Ly, Matthew A. Malkan. 2012-10-24. Unusual Long and Luminous Optical Transient in the Subaru Deep Field. https://doi.org/10.1088/2041-8205%2F760%2F1%2Fl11

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