DUSEL R&D Proposal: R&D Program to Develop Novel Cryogenic Tracking Detectors for Underground Experiments

根据标准太阳模型，太阳的大部分能量是由 pp 聚变反应产生的中微子携带的。精确测量这些中微子的频谱和速率是 2004 年 APS 中微子矩阵报告等定义的三个高度优先目标之一。这些测量将为我们当前的中微子振荡模型提供基本测试，这是对太阳等恒星非标准过程的一个重要限制，并为极低能量中微子相互作用打开一个新窗口，这可能会带来意想不到的发现。该提案要求资金开发一种新型探测器，该探测器将允许实时测量极低能量太阳中微子，低至几个keV，并使用时间投影技术在大体积（超过一吨）中具有出色的空间和能量分辨率。该探测器采用低温流体氖气和氦气作为探测介质，其中存在“电子泡”。沿着探测器中中微子相互作用产生的反冲电子的轨道形成。这些电子气泡在电场中漂移到气体电子倍增器阵列，在那里它们被放大并用商用 CCD 相机进行光学检测。自该研发计划启动以来，教育和推广一直是该研发计划的重点。该探测器的读出概念也可能适用于需要跟踪大量低能粒子的许多其他 DUSEL 实验，例如暗物质跟踪探测器，以及为大型双 β 衰变实验提出的一些方法。他们积极参与针对高中教师和学生的 QuarkNet 项目，将他们的外展活动扩展到与探测器研发项目直接相关的范围，包括其他粒子物理主题以及宇宙射线探测器的实验工作。

According to the Standard Solar Model, most of the energy of the Sun is carried by neutrinos from the pp fusion reaction. A precision measurement of the spectrum and rate of these neutrinos is one of the three high priority goals defined by the 2004 APS Neutrino Matrix report, among others. These measurements will provide a fundamental test of our current model of neutrino oscillations, an important constraint on non-standard processes in stars such as our Sun, and open a new window on very low energy neutrino interactions which may lead to unexpected discoveries.This proposal requests funds to develop a novel detector that will allow a real-time measurement of very low energy solar neutrinos, down to a few keV, with excellent spatial and energy resolution in large volumes (more than a ton), using a time projection technique. The detector uses the cryogenic fluids neon and helium as the detection medium, in which ?electron bubbles? form along the track of a recoil electron produced by a neutrino interaction in the detector. These electron bubbles are drifted in an electric field to an array of Gas Electron Multipliers, where they are amplified and optically detected with commercial CCD cameras. Education and Outreach have been a major emphasis of this R&D program since its inception. This detector?s readout concept may also be suited to a number of other DUSEL experiments requiring tracking of low energy particles in large volumes, for example dark matter tracking detectors, and some of the approaches proposed for a large double beta decay experiment. They are active in the QuarkNet program for high school teachers and students, extending their outreach activities beyond those directly related to this detector R&D program to include other particle physics topics, and experimental work on cosmic ray detectors.