Choi K, Abe K, Haga Y, Hayato Y, Iyogi K, Kameda J, Kishimoto Y, Miura M, Moriyama S, Nakahata M, Nakano Y, Nakayama S, Sekiya H, Shiozawa M, Suzuki Y, Takeda A, Tomura T, Wendell R A, Irvine T, Kajita T, Kametani I, Kaneyuki K, Lee K P, Nishimura Y, Okumura K, McLachlan T, Labarga L, Kearns E, Raaf J L, Stone J L, Sulak L R, Berkman S, Tanaka H A, Tobayama S, Goldhaber M, Carminati G, Kropp W R, Mine S, Renshaw A, Smy M B, Sobel H W, Ganezer K S, Hill J, Hong N, Kim J Y, Lim I T, Akiri T, Himmel A, Scholberg K, Walter C W, Wongjirad T, Ishizuka T, Tasaka S, Jang J S, Learned J G, Matsuno S, Smith S N, Hasegawa T, Ishida T, Ishii T, Kobayashi T, Nakadaira T, Nakamura K, Oyama Y, Sakashita K, Sekiguchi T, Tsukamoto T, Suzuki A T, Takeuchi Y, Bronner C, Hirota S, Huang K, Ieki K, Ikeda M, Kikawa T, Minamino A, Nakaya T, Suzuki K, Takahashi S, Fukuda Y, Itow Y, Mitsuka G, Mijakowski P, Hignight J, Imber J, Jung C K, Yanagisawa C, Ishino H, Kibayashi A, Koshio Y, Mori T, Sakuda M, Yano T, Kuno Y, Tacik R, Kim S B, Okazawa H, Choi Y, Nishijima K, Koshiba M, Totsuka Y, Yokoyama M, Martens K, Marti Ll, Vagins M R, Martin J F, de Perio P, Konaka A, Wilking M J, Chen S, Zhang Y, Wilkes R J
Solar Terrestrial Environment Laboratory, Nagoya University, Nagoya, Aichi 464-8602, Japan.
Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Gifu 506-1205, Japan.
Phys Rev Lett. 2015 Apr 10;114(14):141301. doi: 10.1103/PhysRevLett.114.141301. Epub 2015 Apr 6.
Super-Kamiokande (SK) can search for weakly interacting massive particles (WIMPs) by detecting neutrinos produced from WIMP annihilations occurring inside the Sun. In this analysis, we include neutrino events with interaction vertices in the detector in addition to upward-going muons produced in the surrounding rock. Compared to the previous result, which used the upward-going muons only, the signal acceptances for light (few-GeV/c^{2}-200-GeV/c^{2}) WIMPs are significantly increased. We fit 3903 days of SK data to search for the contribution of neutrinos from WIMP annihilation in the Sun. We found no significant excess over expected atmospheric-neutrino background and the result is interpreted in terms of upper limits on WIMP-nucleon elastic scattering cross sections under different assumptions about the annihilation channel. We set the current best limits on the spin-dependent WIMP-proton cross section for WIMP masses below 200 GeV/c^{2} (at 10 GeV/c^{2}, 1.49×10^{-39} cm^{2} for χχ→bb[over ¯] and 1.31×10^{-40} cm^{2} for χχ→τ^{+}τ^{-} annihilation channels), also ruling out some fraction of WIMP candidates with spin-independent coupling in the few-GeV/c^{2} mass range.
超级神冈探测器(SK)可以通过探测太阳内部弱相互作用大质量粒子(WIMP)湮灭产生的中微子来搜寻WIMP。在本分析中,我们除了考虑周围岩石中产生的向上运动的μ子外,还纳入了探测器中具有相互作用顶点的中微子事件。与仅使用向上运动的μ子的先前结果相比,轻质量(几GeV/c² - 200 GeV/c²)WIMP的信号接受度显著提高。我们对3903天的SK数据进行拟合,以搜寻来自太阳中WIMP湮灭产生的中微子的贡献。我们发现没有明显超过预期大气中微子背景的信号,并且该结果根据不同湮灭通道假设下WIMP - 核子弹性散射截面的上限进行解释。对于质量低于200 GeV/c²的WIMP,我们设定了目前关于自旋相关WIMP - 质子截面的最佳限制(在10 GeV/c²时,对于χχ→bb[上划线]湮灭通道为1.49×10⁻³⁹ cm²,对于χχ→τ⁺τ⁻湮灭通道为1.31×10⁻⁴⁰ cm²),同时也排除了几GeV/c²质量范围内一些具有自旋无关耦合的WIMP候选者。