HALO-1kT at LNGS

LNGS 的 HALO-1kT

• 批准号: SAPPJ-2019-00055
• 负责人: Virtue, Clarence
• 金额: $ 4.74万
• 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: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=691332
• 关键词: HALO; 1kT; LNGS

A type II supernova is powered by the energy liberated in the gravitational collapse of the core of a massive star. Post core collapse, the initially very hot proto-neutron star cools primarily by the emission of neutrinos, of all flavours, roughly equally partitioned. In fact, about 99% of the initial gravitational potential energy is released in a short burst of ~10 MeV neutrinos over a few tens of seconds. The measurement of the time evolution of the neutrino luminosity, flavour partition, and average energy is a direct window into supernova dynamics though a gravitational wave is also anticipated. The nuclear physics of lead, as a target material for the supernova neutrinos, provides for a dominant sensitivity to charged current (CC) interactions of the electron neutrino flux; complete insensitivity to CC interactions of the electron antineutrino flux; and minor sensitivity to all neutrino flavours through neutral current excitation channels. A detailed understanding of supernova dynamics is at the forefront of large-scale computational physics efforts and, when combined with observational data, offers the possibility of extracting fundamental neutrino properties as well as advancing our understanding of the supernova mechanism, heavy element nucleosynthesis, and other astrophysical questions.******HALO-1kT is a proposed lead-based supernova neutrino detector to be constructed at the Laboratori Nazionali del Gran Sasso (LNGS) in Italy. It is an evolution of the successful, but smaller, HALO detector at SNOLAB. HALO-1kT is expected to outperform HALO by a factor of 25 in sensitivity. The scientific collaboration is Canadian-led with major participation by Italian and American groups. This SAP Project grant application is for stable and adequate funding for the Canadian group through the finalization of the full Experimental Proposal; the application for capital funding through CFI; and studies and preparations for experiment deployment. HALO-1kT is timely and possible due to the experience gained in the construction and operation of HALO at SNOLAB; the availability of 1000 tonnes of lead from the OPERA experiment and the enthusiasm at LNGS to re-invigorate their supernova detection capabilities; and the end of the American moratorium on the distribution of He-3 and its availability once again through the DOE Isotope Program. Neither HALO nor HALO-1kT can be claimed to be fully understood and calibrated until the neutrino-lead cross sections are known at supernova-relevant energies. A component of the funds requested here will support a measurement of these cross sections at Oak Ridge National Laboratory's Spallation Neutron Source. However, the bulk of the support for the cross section measurement is coming from a combination of the McDonald Institute (MI), Laurentian University, INFN, University of Washington, LNGS, and SNOLAB and a CFI-JELF submission in preparation. *****

II 型超新星由大质量恒星核心引力塌缩释放的能量提供动力。核心塌陷后，最初非常热的原中子星主要通过中微子的发射而冷却，各种中微子的发射大致相等。事实上，大约 99% 的初始引力势能是在几十秒内约 10 MeV 中微子的短爆发中释放的。中微子光度、味道分配和平均能量随时间演化的测量是了解超新星动力学的直接窗口，尽管也预计会出现引力波。铅作为超新星中微子的目标材料，其核物理特性对电子中微子通量的带电电流 (CC) 相互作用具有显着的敏感性；对电子反中微子通量的 CC 相互作用完全不敏感；通过中性电流激发通道对所有中微子味道具有轻微的敏感性。对超新星动力学的详细了解处于大规模计算物理工作的前沿，当与观测数据相结合时，提供了提取基本中微子特性以及增进我们对超新星机制、重元素核合成和其他方面的理解的可能性。天体物理学问题。******HALO-1kT 是一种拟议的铅基超新星中微子探测器，将在意大利大萨索国家实验室 (LNGS) 建造。它是 SNOLAB 成功但体积更小的 HALO 探测器的演变。 HALO-1kT 的灵敏度预计比 HALO 高 25 倍。 这项科学合作由加拿大主导，意大利和美国团体主要参与。此 SAP 项目赠款申请旨在通过最终确定完整的实验提案，为加拿大小组提供稳定和充足的资金；通过 CFI 申请资本融资；以及实验部署的研究和准备。由于 SNOLAB 在建造和运行 HALO 过程中获得的经验，HALO-1kT 是及时且可行的； OPERA 实验提供了 1000 吨铅，以及 LNGS 重振超新星探测能力的热情；美国暂停 He-3 分发的结束，并再次通过能源部同位素计划获得它。 在了解超新星相关能量的中微子-先导截面之前，HALO 和 HALO-1kT 都不能被认为是完全理解和校准的。 这里请求的资金的一部分将支持橡树岭国家实验室散裂中子源对这些横截面的测量。 然而，对横截面测量的大部分支持来自麦克唐纳研究所 (MI)、劳伦森大学、INFN、华盛顿大学、LNGS 和 SNOLAB 以及正在准备的 CFI-JELF 提交材料。 *****