tokens: The authors are grateful to Makoto Sakuda and Tomonori Totani for valuable comments. We would also like to thank Yusuke Koshio for providing us the data of upper limits from Super-Kamiokande. In this work, numerical computations were partially performed on the supercomputers at Research Center for Nuclear Physics (RCNP) in Osaka University. This work was partially supported by Grants-in-Aids for the Scientific Research (No. 24105008, No. 26104006, No. 26105515, and No. 26870615) from MEXT in Japan.
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