A Proposal for the Borexino Solar Neutrino Experiment

Borexino 太阳中微子实验的提案

• 批准号: 9722552
• 负责人: Frank Calaprice
• 金额: $ 655.6万
• 依托单位: Princeton University
• 依托单位国家: 美国
• 项目类别: Cooperative Agreement
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-08-15 至 2002-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9722552&HistoricalAwards=false
• 关键词: Proposal; Borexino; Solar; Neutrino; Experiment

***9722552CalapriceA detector of solar neutrinos will be constructed for the purpose of measuring the flux of neutrinos from the decay of beryllium-7 in the solar interior. This decay rate is central to understanding the reactions thought to power the sun. The detector is based on the use of approximately 100 tons of liquid scintillator to detect recoil electrons following neutrino-electron interaction in the detector volume. A large array of photomultiplier tubes will sense the light produced in the liquid scintillator by the recoil electron. Because of the very low rate of events, great attention will be paid to reducing backgrounds from cosmic rays and naturally occurring radioisotopes in the detector proper and the surrounding material. In order to reduce cosmic ray backgrounds, the detector will be located underground. The site chosen is the Gran Sasso underground tunnel in Italy. Construction of this detector, known as Borexino, is an international project involving Italy, Germany, and the US. Results from this experiment will test the standard solar model and help place constraints on the mass of the neutrino. These topics are of great current scientific interest because of earlier results which hint at a substantial reduction in the solar neutrino flux due to neutrino mass and oscillations which are thought to take place in the sun whereby neutrinos change from one so-called flavor into another, i.e. from an electron neutrino into a muon or tau neutrino. The joint NSF/DOE Nuclear Science Advisory Committee highlighted this science in its 1996 Long Range Plan. Education of students and postdocs is a strong component of this experimental program.This project is jointly supported by the Division of Physics, Division of Astronomy and the MPS Office of Multidisciplinary Activities.***

*** 9722552钙化太阳中微子的检测器将是为了测量来自太阳能内部铍7衰减的中微子的通量。 这种衰减率对于理解为太阳供电的反应是核心。 该检测器基于使用大约100吨液体闪烁体在检测器体积中中微子 - 电子相互作用后检测后方电子。 大量的光电倍增管会感觉到后坐力电子在液体闪烁体中产生的光。 由于事件的速度非常低，因此将非常关注从适当的探测器和周围材料中降低宇宙射线和自然发生的放射性同位素的背景。 为了减少宇宙射线背景，检测器将位于地下。 选择的地点是意大利的Gran Sasso地下隧道。 该探测器的建设，即Borexino，是一个涉及意大利，德国和美国的国际项目。 该实验的结果将测试标准太阳模型，并有助于对中微子的质量放置约束。 这些主题引起了当前的科学兴趣，因为较早的结果暗示了由于中微子质量和振荡而导致的太阳中微子通量大幅降低，这些质量和振荡被认为是在阳光下发生的，从而将中微子从一种所谓的风味转变为另一种中微子，即将电子中微子从一种电子中性含量转变为一种电子中微子，转变为muon或tau中环。 NSF/DOE联合核科学咨询委员会在其1996年的远程计划中强调了这项科学。 对学生和博士后的教育是该实验计划的重要组成部分。该项目由物理学，天文学和国会议员司和多学科活动办公室共同支持。***