Theoretical Calculations for High Energy Particles in the Atmosphere and in Underground and Accelerator Experiments

大气中、地下和加速器实验中高能粒子的理论计算

• 批准号: 9802403
• 负责人: Mary Hall Reno
• 金额: $ 7.8万
• 依托单位: University of Iowa
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-07-15 至 2002-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9802403&HistoricalAwards=false
• 关键词: Theoretical; Calculations; Energy; Particles; Atmosphere

Calculations will be performed to improve the theoretical predictions for underground and accelerator experiments detecting high energy elementary particle interactions. Consequently, experimental results can be better interpreted whether as tests of aspects of the standard model of strong nuclear, weak and electromagnetic forces or as signals of new physics. Large underground detectors act as neutrino telescopes by detecting the conversions of neutrinos to muons in the water, rock or ice surrounding the detector. Neutrinos produced by galactic or extra-galactic sources travel undeviated to the earth, bringing information about the astrophysical processes that cannot be inferred from studying electomagnetic radiation. Muons and neutrinos are also produced by cosmic ray interactions with air nuclei in the earth's atmosphere. At high energies, charmed particle production and decay in the atmosphere is the dominant terrestrial source of fluxes of muons and neutrinos. A new calculation of the fluxes of muon and neutrinos from the decays of charmed particles that are produced in the atmosphere will be performed using a range of inputs consistent with laboratory measurements of charm production, extrapolated to higher energy. In addition, calculations related to the interpretation of electron neutrino and muon neutrino conversions to charged particles in underground detectors will be refined. The improvements to existing calculations may have an impact on the allowed regions of parameter space in models with neutrino oscillations. A `Monte Carlo` simulation of neutrino production of charm quarks in quantum chromodynamics (QCD) will be developed. QCD is the theoretical description of the strong nuclear force. The Monte Carlo will be used by experimental groups to help them determine strange quark content of the proton.

将进行计算以改进地下和加速器实验探测高能基本粒子相互作用的理论预测。因此，无论是作为对强核力、弱核力和电磁力标准模型的测试，还是作为新物理学的信号，实验结果都可以得到更好的解释。大型地下探测器充当中微子望远镜，探测探测器周围的水、岩石或冰中中微子到μ子的转换。星系或星系外源产生的中微子不会偏离轨道到达地球，带来了通过研究电磁辐射无法推断出的天体物理过程的信息。宇宙射线与地球大气中的空气核相互作用也会产生μ子和中微子。在高能量下，大气中粲粒子的产生和衰变是地球上μ子和中微子通量的主要来源。对大气中产生的粲粒子衰变产生的μ子和中微子的通量进行新的计算，将使用一系列与实验室测量的粲粒子产生相一致的输入，外推到更高的能量。此外，与地下探测器中电子中微子和介子中微子转换为带电粒子的解释有关的计算将得到改进。现有计算方法的改进可能会对中微子振荡模型的参数空间允许区域产生影响。将开发量子色动力学（QCD）中粲夸克产生中微子的“蒙特卡罗”模拟。QCD是对强核力的理论描述。蒙特卡罗将被实验组用来帮助他们确定质子的奇异夸克含量。