Low Energy Nuclear Physics at Princeton - The Borexino Solar Neutrino Experiment

9420867 Calaprice提出了一种用于低能太阳中微子实时测量的新探测器的发展。 为了达到所需的低背景条件，探测器必须位于地下，并由天然放射性纯度的材料制成。 它包括在意大利的Gran Sasso地下实验室进行的大型超纯液体闪烁体操作。 所需的纯度水平是前所未有的，该提案的大部分努力将是通过强大的纯化方法开发特殊的检测器材料。 该探测器将是同类探测器中的第一个，也将是世界上最低的背景探测器。 这里提出的闪烁体探测器，已被称为Borexino实验，旨在以实时模式探测7 Be中微子。 在100吨基准体积中的预期计数率为每天约50个。 本实验的基本要求是铀、钍放射性浓度优于0.5fg/g的大型非分段探测器。 目前正在建造一个质量为4吨的原型探测器，以测试闪烁体的纯度和设计的其他技术方面，最初的研究工作是完成闪烁体容器和闪烁体纯化系统的开发，并将其安装在原型探测器中。 第二项主要工作是利用试验设施研究净化过程的有效性。 然后，研究人员将设计全面的Borexino实验。 ***

9420867 Calaprice The development of a new detector for live-time measurements of low energy solar neutrinos is proposed. To achieve the required low background conditions, the detector must be located underground and be made of materials of natural radiopurity. It consists of a large ultra pure liquid scintillator operation in the Gran Sasso underground laboratory in Italy. The required purity levels are unprecedented and much of the effort of this proposal will be to develop special detector materials by powerful purification methods. This detector will be the first of its kind and will be the lowest background detector in the world. The scintillator detector proposed here, which has become known as the Borexino experiment, is designed to detect the 7Be neutrino in live mode. The expected count rate in the 100 ton fiducial volume is about 50 per day. The essential requirement of this experiment is a large unsegmented detector with uranium and thorium radiopurities of better than 0.5fg/g. A prototype detector with mass of a 4tons is currently under construction to test the purity of the scintillator an other technic aspects of the design, the initial research effort is to complete the development of the scintillator vessel and the scintillator purification system an to install these in the prototype detector. The second major effort will be to employ the test facility to study the effectiveness of purification processes. The researcher will then design the full scale Borexino experiment. ***