학술논문
A Search for Charged Excitation of Dark Matter with the KamLAND-Zen Detector
Document Type
Working Paper
Author
Abe, S.; Asami, S.; Gando, A.; Gando, Y.; Gima, T.; Goto, A.; Hachiya, T.; Hata, K.; Hayashida, S.; Hosokawa, K.; Ichimura, K.; Ieki, S.; Ikeda, H.; Inoue, K.; Ishidoshiro, K.; Kamei, Y.; Kawada, N.; Kinoshita, T.; Koga, M.; Maemura, N.; Mitsui, T.; Miyake, H.; Nakamura, K.; Nakamura, R.; Ono, A.; Ota, N.; Otsuka, S.; Ozaki, H.; Sakai, T.; Sambonsugi, H.; Shimizu, I.; Shirahata, Y.; Shirai, J.; Shiraishi, K.; Suzuki, A.; Suzuki, Y.; Takeuchi, A.; Tamae, K.; Ueshima, K.; Wada, Y.; Watanabe, H.; Yoshida, Y.; Obara, S.; Chernyak, D.; Kozlov, A.; Yoshida, S.; Umehara, S.; Takemoto, Y.; Fushimi, K.; Hirata, S.; Ichikawa, A.; Nakamura, K. Z.; Yoshida, M.; Berger, B. E.; Fujikawa, B. K.; Grant, C.; Li, A.; Learned, J. G.; Maricic, J.; Axani, S.; Winslow, L. A.; Fu, Z.; Efremenko, Y.; Karwowski, H. J.; Markoff, D. M.; Tornow, W.; ODonnell, T.; DellOro, S.; Detwiler, J. A.; Enomoto, S.; Decowski, M. P.
Source
Subject
Language
Abstract
There are many theories where a dark matter particle is part of a multiplet with an electrically charged state. If WIMP dark matter ($\chi^{0}$) is accompanied by a charged excited state ($\chi^{-}$) separated by a small mass difference, it can form a stable bound state with a nucleus. In supersymmetric models, the $\chi^{0}$ and the $\chi^{-}$ could be the neutralino and a charged slepton, such as the neutralino-stau degenerate model. The formation binding process is expected to result in an energy deposition of {\it O}(1--10 MeV), making it suitable for detection in large liquid scintillator detectors. We describe new constraints on the bound state formation with a xenon nucleus using the KamLAND-Zen 400 Phase-II dataset. In order to enlarge the searchable parameter space, all xenon isotopes in the detector were used. For a benchmark parameter set of $m_{\chi^{0}} = 100$ GeV and $\Delta m = 10$ MeV, this study sets the most stringent upper limits on the recombination cross section $\langle\sigma v\rangle$ and the decay-width of $\chi^{-}$ of $2.0 \times 10^{-31}$ ${\rm cm^3/s}$ and $1.1 \times 10^{-18}$ GeV, respectively (90\% confidence level).