Diffuse supernova neutrino background is detectable in Super-Kamiokande
Diffuse supernova neutrino background is detectable in Super-Kamiokande
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DOI：
10.1103/physrevd.79.083013
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发表时间：
2008-12
影响因子：
5
通讯作者：
S. Horiuchi;J. Beacom;E. Dwek
中科院分区：
文献类型：
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作者：
S. Horiuchi;J. Beacom;E. Dwek
扩散超新星中微子背景（DSNB）提供了一个直接的机会，研究从核心坍缩超新星的MeV热中微子的排放。DSNB是恒星和中微子物理学的强大探测器，前提是核心坍缩速率足够大，其不确定性足够小。为了评估DSNB所支持的重要物理学，我们从霍普金斯和Beacom（2006）的宇宙星星形成历史开始，并通过与超新星速率、河外背景光和恒星质量密度的交叉检查来确认其标准化和演化。我们发现一个足够的核心崩溃率与小的不确定性，转化为{+-}40%的DSNB事件谱的变化。考虑到有效温度在4-6 MeV之间的热中微子谱，预测的DSNB在2003年由Super-Kamiokande获得的上限以下的4-2倍之内。此外，使用钆增强的Super-Kamiokande将显著改善探测前景：本底将显著降低，通量和不确定性收敛于较低的阈值能量，并且在10-26 MeV的能量范围内预测事件率为1.2-5.6事件/年{sup-1}。这些结果表明，超级神冈探测器即将探测到DSNB，以及它在研究恒星和中微子物理学方面令人兴奋的前景。
The diffuse supernova neutrino background (DSNB) provides an immediate opportunity to study the emission of MeV thermal neutrinos from core-collapse supernovae. The DSNB is a powerful probe of stellar and neutrino physics, provided that the core-collapse rate is large enough and that its uncertainty is small enough. To assess the important physics enabled by the DSNB, we start with the cosmic star formation history of Hopkins and Beacom (2006) and confirm its normalization and evolution by cross-checks with the supernova rate, extragalactic background light, and stellar mass density. We find a sufficient core-collapse rate with small uncertainties that translate into a variation of {+-}40% in the DSNB event spectrum. Considering thermal neutrino spectra with effective temperatures between 4-6 MeV, the predicted DSNB is within a factor 4-2 below the upper limit obtained by Super-Kamiokande in 2003. Furthermore, detection prospects would be dramatically improved with a gadolinium-enhanced Super-Kamiokande: the backgrounds would be significantly reduced, the fluxes and uncertainties converge at the lower threshold energy, and the predicted event rate is 1.2-5.6 events yr{sup -1} in the energy range 10-26 MeV. These results demonstrate the imminent detection of the DSNB by Super-Kamiokande and its exciting prospects for studying stellar and neutrino physics.