射电天文研究室知识库

为了开拓短厘米波单天线星际分子的观测和研究，在乌鲁木齐天文站25m射电望远镜13mm低温制冷接收机的基础上，配置了声表面波频谱仪和谱线数据采集系统，组成了13mm低温致冷谱线接收机。接收机前端是一个工作在低温20K的低噪声放大器，本振是22GHz的锁相源。接收机的平均噪声温度为50K。后端是一个宽带的(40MHz)高分辨率(40kHz)的声表波频谱仪。利用这套系统观测了一批已知的水脉泽源，观测系统正常，结果合理。观测结果表明．乌鲁木齐天文站良好的站址和25m射电望远镜给厘米波段星际分子谱线观测提供了一个很好的条件。

For the spectral line observations in short centimeter wavelength region with a single dish , a SAW(surface acoustic wave)spect rometer has been installed on the Urumqi 25m radio telescope. Together with a 13mm cryogenically-cooled receiver , an analytical sy stem of spectrum has been built with low noise temperature. The front-end is a low noise amplifier operating at the temperature of 20K and the PLO uses a 22GHz phase locked oscillator. An average noise temperature of 50K for this receiver sy stem was measured. The back-end is a SAW spectrometer with wide band of 40MHz and frequency resolution of 40kHz. Many known H2O maser sources were observed with reasonable results .The site and facilities at Urumqi Astronomical Station provide excellent conditions for the spectral line observations in centimeter wavelength region .