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.***

***9722552Calaprice 将建造一个太阳中微子探测器，用于测量太阳内部铍 7 衰变产生的中微子通量。 这种衰变率对于理解为太阳提供动力的反应至关重要。 该探测器基于使用大约 100 吨的液体闪烁体来探测探测器体积中中微子-电子相互作用后的反冲电子。 大量光电倍增管将感测反冲电子在液体闪烁体中产生的光。 由于事件发生率非常低，因此将高度重视减少探测器本身和周围材料中宇宙射线和自然产生的放射性同位素的背景。 为了减少宇宙射线背景，探测器将位于地下。 所选地点是意大利的格兰萨索地下隧道。 该探测器的建造被称为 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限制中微子的质量。 这些主题目前具有很大的科学意义，因为早期的结果暗示，由于中微子质量和振荡，太阳中微子通量大幅减少，中微子质量和振荡被认为发生在太阳中，中微子从一种所谓的味道变成了另一种味道，即从电子中微子转变为μ子或τ子中微子。 NSF/DOE 联合核科学咨询委员会在其 1996 年长期计划中强调了这一科学。 学生和博士后教育是该实验项目的重要组成部分。该项目由物理系、天文学系和公安部多学科活动办公室共同支持。***