Reanalysis of the 1992 South Pole Millimetre-Wavelength Atmospheric Opacity Data

Publications of the Astronomical Society of Australia

Richard A. Chamberlin¹ 

关键词: instrumentation: miscellaneous;    methods: data analysis;    site testing;    atmospheric effects;   

DOI  :  10.1071/AS03012

学科分类：天文学(综合)

来源: CSIRO

【 摘 要 】

In 1992 an NRAO 225-GHz site survey heterodyne radiometer was placed at the Geographical South Pole. The instrument operated over an entire annual cycle and provided direct measurements of the millimetre-wave sky brightness temperature as a function of zenith angle. Interpreted in a single-slab ‘skydip’ radiation transfer model of the atmosphere, these sky brightness measurements provided a time series of the millimetre atmospheric opacity. Statistics derived from this opacity time series were important for making comparisons with other candidate millimetre and sub-millimetre wave astronomy sites. This paper reexamines the 1992 measurements and the original analysis. Details of the skydip fit model, radiometer gain error, instrument stability, and a mid-season replacement to a window in the instrument enclosure combined to cause a modest under-reporting of the atmospheric opacity in previous reports. Unchanged are earlier conclusions that dry air makes a significant contribution to the total opacity at 225 GHz.

【 授权许可】

Unknown