Acquisition of Low Background High-Resolution Gamma Spectrometers for Research and Undergraduate Student Training

采购低本底高分辨率伽马能谱仪用于研究和本科生培训

• 批准号: 2203667
• 负责人: James Kaste
• 金额: $ 24.86万
• 依托单位: College of William and Mary
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-15 至 2025-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2203667&HistoricalAwards=false
• 关键词: Acquisition; Low; Background; Resolution; Gamma

This grant will support the acquisition of two high-resolution gamma spectrometers for faculty research and undergraduate student training in the Geology Department and Environmental Science Program at William & Mary. The spectrometers will enable precise measurements of naturally occurring gamma-emitting radionuclides from isotopes of uranium, thorium, potassium, and radium present in rocks and sediments worldwide, along with artificial isotopes of cesium and plutonium in air, soil, and sediment generated by the nuclear fuel and weapons processes. Importantly, these instruments will give us the capability to date sedimentary layers and thus be used to help reconstruct regional pollution histories and better understand Arctic climate change. Because sample preparation is simple for gamma spectrometry and the instruments have long-term stability, the spectrometers will be used to support undergraduate research training, augment undergraduate courses and laboratory exercises, and will provide educational outreach opportunities to faculty and students at Thomas Nelson Community College, a local two-year community college.The gamma spectrometers acquired will support a wide range of ongoing research projects at William & Mary and the Virginia Institute of Marine Sciences by providing precise ultra-trace measurements of radionuclide concentrations in environmental samples. The design of the instrumentation allows for optionally analyzing a single sample from opposing sides using both detectors and timed measurements to record coincident and anti-coincident pulses, a configuration that that will enable greatly improved detection limits for cosmogenic 22Na and for radionuclide measurements on small sample masses required by sediment core research. A major goal of existing research at William & Mary is to generate high-resolution reconstructions of past climate changes in the Pleistocene and Holocene at sites in Greenland, Norway, Svalbard, and the Faroe Islands from lake sediment cores. A second project that will be supported by this equipment acquisition aims to better understand radon sources in the Atlantic Coastal Plain, an area previously believed to have low uranium and radon potential. This instrumentation will support these two projects, and broadly equip researchers at William & Mary and the Virginia Institute of Marine Sciences studying salt marsh development and sedimentation in continental margin environments.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

这笔拨款将支持获得两台高分辨率伽马光谱仪，用于威廉玛丽大学地质系和环境科学项目的教师研究和本科生培训。光谱仪将能够精确测量世界各地岩石和沉积物中存在的铀、钍、钾和镭同位素中自然产生的伽马发射放射性核素，以及空气、土壤和核燃料和武器加工产生的沉积物中铯和钚的人工同位素。重要的是，这些仪器将使我们能够确定沉积层的年代，从而帮助重建区域污染历史，更好地了解北极气候变化。由于伽马能谱法样品制备简单，仪器具有长期稳定性，光谱仪将用于支持本科生研究培训，增加本科课程和实验室练习，并将为托马斯纳尔逊社区学院（当地两年制社区学院）的教职员工和学生提供教育推广机会。获得的伽马能谱仪将通过提供环境样品中放射性核素浓度的精确超痕量测量，支持威廉玛丽和弗吉尼亚海洋科学研究所正在进行的广泛研究项目。仪器的设计允许选择性地分析来自不同侧面的单个样品，同时使用探测器和定时测量来记录一致和反一致脉冲，这种配置将大大提高宇宙起源22Na的检测极限，以及沉积物岩心研究所需的小样本质量的放射性核素测量。威廉玛丽研究所现有研究的一个主要目标是利用湖泊沉积物岩心对格陵兰岛、挪威、斯瓦尔巴群岛和法罗群岛的更新世和全新世的气候变化进行高分辨率重建。这次设备采购将支持的第二个项目旨在更好地了解大西洋沿岸平原的氡源，该地区以前被认为铀和氡的潜力很低。该仪器将支持这两个项目，并广泛装备威廉玛丽和弗吉尼亚海洋科学研究所研究大陆边缘环境中盐沼发展和沉积的研究人员。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。