Neutron Detector R&D for HALO-1kT TDR

中子探测器 R

• 批准号: SAPPJ-2017-00041
• 负责人: Virtue, Clarence
• 金额: $ 2.91万
• 依托单位: Laurentian University of Sudbury
• 依托单位国家: 加拿大
• 项目类别: Subatomic Physics Envelope - Project
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=667833
• 关键词: Neutron; Detector; R&D; HALO; 1kT

The Helium and Lead Observatory (HALO) is a low cost, high livetime, low maintenance supernova detector running at SNOLAB since May 2012. The use of lead as the target material gives HALO unique sensitivity to electron neutrinos, complementary to other detectors worldwide. HALO is a member of the SuperNova Early Warning System. Support is requested for the ongoing operation and maintenance of HALO.******A type II supernova is powered by the gravitational collapse of the core of a massive star. The hot proto-neutron star cools primarily by the emission of neutrinos, of all flavours, in some tens of seconds. About 99% of the gravitational potential energy liberated emerges as ~10MeV neutrinos. Conceptually, HALO is 80 tonnes of lead instrumented with He-3 neutron detectors. Neutrinos from the supernova excite lead nuclei via both charged current (CC) and neutral current weak interactions to states from which one or two neutrons are ejected. The detection of these neutrons in HALO's He-3 detectors signals a galactic supernova. The time evolution of the luminosity, flavours and average neutrino energy give a direct window into supernova dynamics. The neutron excess of lead provides for a dominant sensitivity to CC interactions of the νe flux. Modeling of supernovae combined with observational data, offers the possibility of extracting fundamental neutrino properties as well as advancing our understanding of the supernova mechanism. HALO at SNOLAB is modest in size and limited by statistics, more so the further the supernova, or the lower the neutrino energy. The decommissioning of the OPERA detector at LNGS in Italy makes 1.3 kT of lead available for the construction of a new detector, HALO-1kT, up to 30 times more sensitive than HALO. Also the new availability of He-3 from the US DOE opens a path to build more He-3 neutron counters. Support is requested for proof of principle measurements for the studies necessary to write a Technical Design Report.******We also wish to join the COHERENT Collaboration to make the first measurement of neutrino-lead cross sections at supernova-relevant energies. The Spallation Neutron Source (SNS) at Oak Ridge National Laboratory produces intense pulses of neutrinos from pion and muon decay at rest. The existing HALO development data acquisition system, together with spare He-3 neutron detectors would enable us to easily measure the neutrino-lead cross section. Support is requested to transport this hardware to and from the SNS. This measurement would complete the calibration of HALO as well as help define the capabilities of HALO-1kT.******Existing and planned neutrino detectors are only sensitive to supernovae occurring within our Galaxy. Only 2-3 are expected per century, so it is important to observe the next one with many detectors of diverse characteristics and sensitivities. Much was learnt from the 20 events from SN 1987A. Much more should be possible from the next galactic supernova.**

氦气观测（Halo）是一个低成本的材料，它为全球其他探测器提供了独特的敏感性中微子。 **** d由巨大的恒星的核心倒塌。 Halo是80吨的铅仪器，该铅具有来自超新星铅核的He-3中子检测器中微子，均带电电流（CC），并从halo的He-3中射出了中性的中性弱相互作用。探测器信号是银河系超新星。机构。构建更多的HE-3中子柜员，以撰写针对技术设计报告的原理测量橡树岭国家实验室的散布源（SNS）在re reto中产生了中微子的强烈脉冲卤素1kt的能力。 SN 1987a。