羟基分子射电谱线的一种观测处理方法

METHODS USED IN THE OBSERVATION AND DATA REDUCTION OF THE RADIO SPECTRAL LINES OF OH MOLECULES

本文主要阐述用上海天文台的25米射电望远镜和北京大学的128路数字自相关频谱仪在我国首次进行羟基分子射电谱线观测的处理方法,包括自相关频谱仪、频率开关方法和本地静止标准等.文中并以羟基源W3、W12和哈雷彗星的射电谱线观测处理结果为例,着重论证了频率开关法就是频域内的调制法,包括调制、解调、积分和基线校准等一系列步骤.

In March-April of 1986, we carried out the first observation of the radio OH line in China at Meixian County, Shannxi Province, using the 25m radio telescope of Shanghai Observatory and an 128-channel autocorrelation spectrometer of Peking University. Here methods used in the observation and data processing of the radio spectral line of OH molecules are introduced, including the autocorrelation spectrometer, the frequency switching and the determination of the Local Standard of Rest (LSR). We take the frequency switching method as a modulation method in frequency domain, which consists of modulation, demodulation integration and baseline fitting.