Neutrino Physics: Solar - Borexino

中微子物理：太阳能 - Borexino

• 批准号: 1413031
• 负责人: ROBERT VOGELAAR
• 金额: $ 65.54万
• 依托单位: Virginia Polytechnic Institute and State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-01 至 2020-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1413031&HistoricalAwards=false
• 关键词: Neutrino; Physics; Solar; Borexino

Solar neutrino research has already discovered massive neutrinos and flavor mixing, and is moving into an era where precision measurements can tell us about the inner workings of the Sun. The carbon-nitrogen-oxygen (CNO) cycle is one of the fusion reactions by which stars convert hydrogen to helium, releasing electron-neutrinos. Should this next period allow the Borexino detector to measure the CNO neutrino flux sufficiently well to infer the metallicity (the abundance of elements other than hydrogen or helium) of the sun's interior, it could test the fundamental assumption of homogeneity in the sun and provide crucial information regarding opacities in the solar interior that are important for helioseismology. Such studies could thus have a great impact on our understanding of the sun, stellar astrophysics, the link between planetary and stellar formation, as well as basic neutrino physics. This award provides funding for the continuing role of Virginia Tech in the Borexino experiment, the world's purest large-volume liquid scintillator detector located at the Gran Sasso National Laboratory in Italy, designed to measure the principle components of the neutrino spectrum coming from the Sun as it converts hydrogen into helium through fusion. They have measured the 7-Be, 8-B, and pep neutrino fluxes from the Sun, and set a limit on the CNO neutrino flux. The next three-year period with ultra-low background requires re-calibration to verify these results, and to prepare the collaboration to move into a new 'CNO focused' phase. The principle physics goals are 1) measurement of the CNO neutrino flux, 2) more precise results for the 7-Be and pep neutrino flux, and 3) a better result for the pp neutrino flux. The broader impact on science, technology and outreach that is expected from the program includes: the training of graduate and undergraduate students in current topical physics research; experience with deployment and utilization of ultra-clean calibration techniques; presentations of this research program to undergraduates, through research projects, student presentations, lectures, and problems - exposing the next generation of scientists from multiple fields to the excitement of astroparticle physics; and a broad engagement of the neutrino community through their Center for Neutrino Physics.

太阳中微子研究已经发现了巨大的中微子和味道混合，并且正在进入一个精确测量可以告诉我们太阳内部运作的时代。碳-氮-氧（CNO）循环是恒星将氢转化为氦并释放电子中微子的聚变反应之一。如果下一个周期让 Borexino 探测器能够足够好地测量 CNO 中微子通量，以推断太阳内部的金属丰度（氢或氦以外的元素丰度），它可以测试太阳均匀性的基本假设，并提供关键的信息。有关太阳内部不透明度的信息对日震学很重要。因此，此类研究可能会对我们对太阳、恒星天体物理学、行星与恒星形成之间的联系以及基本中微子物理学的理解产生巨大影响。该奖项为弗吉尼亚理工大学在 Borexino 实验中继续发挥作用提供资金，Borexino 实验是世界上最纯净的大体积液体闪烁体探测器，位于意大利格兰萨索国家实验室，旨在测量来自太阳的中微子光谱的主要成分它通过聚变将氢转化为氦。他们测量了来自太阳的 7-Be、8-B 和 pep 中微子通量，并对 CNO 中微子通量设定了限制。未来三年的超低背景需要重新校准来验证这些结果，并为合作进入新的“以 CNO 为重点”阶段做好准备。主要物理目标是 1) 测量 CNO 中微子通量，2) 更精确的 7-Be 和 pp 中微子通量结果，以及 3) 更好的 pp 中微子通量结果。该计划预计对科学、技术和推广产生更广泛的影响，包括：对研究生和本科生进行当前专题物理研究的培训；具有部署和使用超净校准技术的经验；通过研究项目、学生演示、讲座和问题向本科生介绍该研究计划——让来自多个领域的下一代科学家接触到天体粒子物理学的兴奋；以及中微子界通过中微子物理中心的广泛参与。