Study on the accidental background of the JSNS$^2$ experiment

Lee, D. H.; Ajimura, S.; Cheoun, M. K.; Choi, J. H.; Choi, J. Y.; Dodo, T.; Goh, J.; Haga, K.; Harada, M.; Hasegawa, S.; Hiraiwa, T.; Hwang, W.; Jang, H. I.; Jang, J. S.; Jeon, H.; Jeon, S.; Joo, K. K.; Jung, D. E.; Kang, S. K.; Kasugai, Y.; Kawasaki, T.; Kim, E. J.; Kim, J. Y.; Kim, S. B.; Kim, W.; Kinoshita, H.; Konno, T.; Lim, I. T.; Little, C.; Marzec, E.; Maruyama, T.; Masuda, S.; Meigo, S.; Monjushiro, S.; Moon, D. H.; Nakano, T.; Niiyama, M.; Nishikawa, K.; Pac, M. Y.; Park, H. W.; Park, J. S.; Park, R. G.; Peeters, S. J. M.; Rott, C.; Sakai, K.; Sakamoto, S.; Shima, T.; Shin, C. D.; Spitz, J.; Suekane, F.; Sugaya, Y.; Suzuya, K.; Taira, M.; Yamaguchi, Y.; Yeh, M.; Yeo, I. S.; Yoo, C.; Yu, I.

doi:10.1140/epjc/s10052-024-12778-7

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Study on the accidental background of the JSNS$^2$ experiment

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Abstract

JSNS 2 (J-PARC Sterile Neutrino Search at J-PARC Spallation Neutron Source) is an experiment that searches for sterile neutrinos via the observation of $\overline{v}$ μ → $\overline{v}$ e appearance oscillations using muon decay-at-rest neutrinos. The JSNS 2 experiment performed data taking from 2021. In this manuscript, a study of the accidental background is presented. The rate of the accidental background is (9.29 ± 0.39) x 10 –8 /spill with 0.75 MW beam power and comparable to the expected number of signal events.

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Lee, D. H., Ajimura, S., Cheoun, M. K., Choi, J. H., Choi, J. Y., Dodo, T., Goh, J., Haga, K., Harada, M., Hasegawa, S., Hiraiwa, T., Hwang, W., Jang, H. I., Jang, J. S., Jeon, H., Jeon, S., Joo, K. K., Jung, D. E., Kang, S. K., Kasugai, Y., Kawasaki, T., Kim, E. J., Kim, J. Y., Kim, S. B., Kim, W., Kinoshita, H., Konno, T., Lim, I. T., Little, C., Marzec, E., Maruyama, T., Masuda, S., Meigo, S., Monjushiro, S., Moon, D. H., Nakano, T., Niiyama, M., Nishikawa, K., Pac, M. Y., Park, H. W., Park, J. S., Park, R. G., Peeters, S. J. M., Rott, C., Sakai, K., Sakamoto, S., Shima, T., Shin, C. D., Spitz, J., Suekane, F., Sugaya, Y., Suzuya, K., Taira, M., Yamaguchi, Y., Yeh, M., Yeo, I. S., Yoo, C., Yu, I.. 2024-04-22. Study on the accidental background of the JSNS$^2$ experiment. https://doi.org/10.1140/epjc%2Fs10052-024-12778-7

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