225-GHz atmospheric opacity of the South Pole sky derived from continual radiometric measurements of the sky-brightness temperature.
225-GHz atmospheric opacity of the South Pole sky derived from continual radiometric measurements of the sky-brightness temperature.
复制标题
南极天空的 225 GHz 大气不透明度源自对天空亮度温度的连续辐射测量。
作者：
Richard Chamberlin;John Bally
我们报告测量的大气不透明度的南极在225 GHz的期间从第3天到第180天在1992年。这些不透明度数据来自连续辐射测量的天空亮度温度作为天顶角的函数。这些辐射测量是用从国家射电天文台借来的225千兆赫外差大气辐射计进行的。这台辐射计以前曾被用来表征其他候选毫米和亚毫米射电望远镜站点。1992年第3天至第70天，大气不透明度在0.098空气质量（-1）以下的时间占75%，在第70天至第180天，大气不透明度在0.055空气质量（-1）以下的时间占75%。因此，我们的数据表明，南极是一个很好的网站进行毫米和亚毫米波长射电天文学。
We report measurements of the atmospheric opacity of the South Pole at 225 GHz for the period from day 3 to day 180 in 1992. These opacity data were derived from continual radiometric measurements of the sky-brightness temperature as a function of the zenith angle. These radiometric measurements were performed with a 225-GHz heterodyne atmospheric radiometer on loan from the National Radio Astronomy Observatory. This radiometer was previously used to characterize other candidate millimeter and submillimeter radio-telescope sites. We found that the atmospheric opacity was below 0.098 air mass(-1) 75% of the time from day 3 to day 70 in 1992, and below 0.055 air mass(-1) 75% of the time from day 70 to day 180 in 1992. Thus, our data demonstrate that the South Pole is an excellent site for performing millimeter-and submillimeter-wavelength radio astronomy.