从海量的天文观测数据中快速搜寻罕见的快速射电暴(Fast Radio Burst,FRB)事件,干扰缓解是其中一项关键而具有挑战的工作.射频干扰(Radio Frequency Interference,RFI)会淹没真实的天文事件,还会导致搜寻管线输出大量的假阳性候选体.由于干扰来源及其种类的复杂性,目前并没有一种通用的方法可以解决这个问题.为了降低干扰对FRB观测搜寻的影响,分析和研究了南山26 m射电望远镜L波段观测数据中的干扰情况,针对主要的窄带干扰和宽带干扰建立了3层次的干扰缓解处理流程,从而有效缓解了观测数据的干扰污染情况.将该流程嵌入到FRB色散动态谱搜寻(Dispersed Dynamic Spectra Search,DDSS)管线中,实验结果表明,搜寻管线的检测率和检测精度得到了进一步的提高.该方法为FRB观测数据干扰缓解处理提供了有价值的参考.
Radio Frequency Interference Mitigation Methods for Fast Radio Burst Observational Data
To quickly search for rare fast radio bursts(FRBs)from massive astronomical observation data,Radio Frequency Interference(RFI)mitigation is one of the crutial and challenging tasks.RFI will produce a large number of false positive candidates,and even submerge real astronomical events.Due to the complexity of the sources and types of RFI,there is currently no universal method to solve this problem.In order to reduce the impact of RFI on FRB search,the RFI in L band observational data of the Nanshan 26 m radio telescope was analyzed and studied.A three-level RFI mitigation procedure was established for the main narrowband RFI and broadband RFI,which effectively alleviated the RFI pollution of observational data.Embedding this procedure into the FRB DDSS(Dispersion Dynamic Spectra Search)pipeline,experimental results show that the detection rate and accuracy of the search algorithm have been further improved.This method provides valuable reference for RFI mitigation of FRB observational data.
radio continuum:transientsradio frequency interference(RFI)methods:data analysis
万方数据
维普
