Low-Frequency Measurements of the Cosmic Microwave Background Radiation

宇宙微波背景辐射的低频测量

• 批准号: 9018395
• 负责人: George Smoot
• 金额: $ 30.15万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-01-01 至 1993-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9018395&HistoricalAwards=false
• 关键词: Low; Frequency; Measurements; Cosmic; Microwave

This project will make cosmological measurements of two distinctly different types. 1. The experimenters will make cosmic microwave background radiation (CMBR) measurements of the absolute brightness of the sky above South Pole at three frequencies, 1.0, 1.5 and 7.5 GHz. Similar measurements were made at the higher two frequencies from Pole in 1989, but the 1.0 GHz radiometer is new. The purpose is to determine if there are deviations from the CMBR temperature of 2.735 K which has been measured at higher frequencies, most notably by the new NASA satellite Cosmic Background Explorer (COBE). Deviations, at different wavelengths, from the 2.736 K figure would indicate that there has been an input of significant energy into the universe since the time of the big bang. 2. They will attempt to measure microwave radiation coming upwards from the polar ice sheet, which is over two kilometers thick at South Pole. It has been hypothesized that extremely energetic neutrinos that have passed entirely through the Earth can interact in the ice, or rocks just below, and cause a electromagnetic shower that could result in detectable radio emissions. If this is true, then the polar ice sheet could be used as a vast detector for the new field of neutrino astronomy. This project is jointly funded by the Divisions of Polar Programs and Astronomy.

该项目将对两个明显的宇宙学测量 不同的类型。 1. 实验者将使宇宙微波背景辐射 天空绝对亮度的辐射测量 在1.0、1.5和7.5千兆赫三个频率上。 在较高的两个频率下进行了类似的测量， 极在1989年，但1.0千兆赫辐射计是新的。 目的是 以确定是否存在与CMBR温度的偏差， 2.735 K，在更高的频率下测量，最明显的是 宇宙背景探测器（COBE） 在不同波长处，与2.736 K数值的偏差将 这表明，已经有大量能量投入到 从大爆炸开始的宇宙。 2. 他们将尝试测量来自 从两公里以上的极地冰盖向上延伸 在南极很厚。 据推测， 完全穿过地球的高能中微子， 在冰层或岩石中相互作用， 电磁簇射可能导致可探测到的无线电 排放 如果这是真的，那么极地冰盖可以用来 作为中微子天文学新领域的巨大探测器。 该项目由极地计划部门共同资助 和天文学。