Long Term Modulation of the Galactic Cosmic Radiation

银河宇宙辐射的长期调制

• 批准号: 0349651
• 负责人: Frank McDonald
• 金额: $ 24.63万
• 依托单位: University of Maryland, College Park
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-08-01 至 2008-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0349651&HistoricalAwards=false
• 关键词: Long; Term; Modulation; Galactic; Cosmic

The investigators will use the understanding gained from satellite and other contemporary investigations of the cosmic radiation and its interaction with the heliospheric magnetic field, to investigate the temporal variability of the cosmic ray modulation over the past 10,000 years. Current evidence indicates that solar activity exhibits a "long" periodicity of about 2200 years, and the investigation is expected to yield important results regarding the origin of the heliospheric magnetic field, and its quantitative variability over time. This activity may have considerable impact upon cosmic ray theory, solar physics, and aspects of space weather. The research will use cosmogenic data, and mathematical solutions of the cosmic ray transport equation, to investigate the long term modulation processes to infer the state of the heliosphere and of the solar magnetic field. The investigation will (1) develop analytical techniques to provide better resolution of the 11 year variation in beryllium-10 isotope data, and to better remove geomagnetic effects from the carbon-14 record; (2) use the cosmogenic data, and all available solar proxies, to study the associations between the cosmic ray modulation, and solar activity throughout the interval 850-1950 A.D.; (3) use the understanding gained in (1) and (2) to study the modulation processes for the past 10,000 years; and (4) assess the feasibility of making high precision measurements of the beryllium-10 production since 1951, to allow detailed comparison with the neutron monitor record and to better understand the coupling between beryllium-10, carbon-14, and galactic cosmic ray observations. A major outcome will be strengthened collaboration among the cosmic ray, solar, and cosmogenic research communities. The cosmogenic data are one of the few quantitative measurements available to study solar processes in the past, and their effects at Earth, and the quantitative information that will be obtained on the heliospheric magnetic fields is expected to be of interest to disciplines concerned with climatic, geological, and biological changes during the Holocene. Quantifying the heliospheric effects in the past will assist the prediction of the solar effects upon our technological infrastructure in the future.

调查人员将利用从卫星和其他当代宇宙辐射及其与日光层磁场相互作用的调查中获得的了解，调查过去10，000年来宇宙射线调制的时间变化。目前的证据表明，太阳活动具有约2200年的“长”周期性，预计调查将产生有关日光层磁场起源及其随时间变化的定量变化的重要结果。这一活动可能对宇宙射线理论、太阳物理学和空间天气的各个方面产生相当大的影响。这项研究将使用宇宙起源数据和宇宙射线传输方程的数学解，调查长期调制过程，以推断日光层和太阳磁场的状态。调查将（1）开发分析技术，以提供铍-10同位素数据中11年变化的更好分辨率，并更好地从碳-14记录中消除地磁效应;（2）使用宇宙成因数据和所有可用的太阳代用指标，研究宇宙射线调制与整个公元850-1950年期间太阳活动之间的关系; (3)利用在（1）和（2）中获得的理解来研究过去10，000年的调制过程;（4）评估对1951年以来铍-10的生产进行高精度测量的可行性，以便能够与中子监测器记录进行详细比较，并更好地了解铍-10、碳-14和银河宇宙射线观测之间的耦合。一个主要成果将是加强宇宙射线、太阳和宇宙成因研究界之间的合作。宇宙成因的数据是为数不多的定量测量，可用于研究太阳在过去的过程中，他们在地球上的影响，并将获得的日光层磁场的定量信息，预计将感兴趣的学科与气候，地质和生物变化在全新世。对过去日光层效应的量化将有助于预测未来太阳对我们技术基础设施的影响。