SGER: Determination of Atmospheric Neutron Attenuation Length at Geomagnetic Cutoff Rigidity of 17-18 Gigavolt (GV) in Southeast Asia

SGER：东南亚地磁截止刚度为 17-18 吉伏 (GV) 时大气中子衰减长度的测定

• 批准号: 0081403
• 负责人: Marek Zreda
• 金额: $ 2万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-06-15 至 2002-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0081403&HistoricalAwards=false
• 关键词: SGER; Determination; Atmospheric; Neutron; Attenuation

The proposed study aims to improve surface exposure dating using in-situ accumulation of cosmogenic isotopes by improving knowledge of the spatial variability of the cosmic-ray intensity with geomagnetic cutoff rigidity (a measure of geomagnetic intensity) and with elevation. The proposal is to conduct a survey of the neutron intensity at the rigidity greater than 17 GV and at altitudes up to 6 km. The work will be conducted in southeast Asia (probably in Thailand), the only location with rigidities above 17 GV. The proponents will measure the neutron intensity using a small aircraft flying at a constant altitude. The results will be used to determine the neutron attenuation length (the function that relates neutron intensity to elevation) for this rigidity. The value will then be used with their other survey results and with other published data to determine how the attenuation length varies with the cutoff rigidity (or with geomagnetic latitude). The final goal of the project will be the construction of improved formulations for scaling production rates of cosmogenic isotopes from one location to any other arbitrary location.

拟议研究的目的是通过提高对宇宙射线强度随地磁截止刚度（地磁强度的一种量度）和海拔的空间变异性的认识，利用宇宙成因同位素的原地积累改进表面暴露年代测定。建议在刚度大于17 GV和高度高达6 km的情况下进行中子强度调查。这项工作将在东南亚（可能在泰国）进行，这是刚性在17 GV以上的唯一位置。支持者将使用一架在恒定高度飞行的小型飞机来测量中子强度。结果将用于确定该刚度的中子衰减长度（将中子强度与高程关联的函数）。然后，该值将与他们的其他调查结果和其他公布的数据一起使用，以确定衰减长度如何随截止刚度（或地磁纬度）变化。该项目的最终目标将是构建改进的配方，用于将宇宙成因同位素的生产率从一个地点扩展到任何其他任意地点。