A Hierarchical Method for Locating the Interferometric Fringes of Celestial Sources in the Visibility Data

Abstract

In source detection in the Tianlai project, locating the interferometric fringe in visibility data accurately will influence downstream tasks drastically, such as physical parameter estimation and weak source exploration. Considering that traditional locating methods are time-consuming and supervised methods require a great quantity of expensive labeled data, in this paper, we first investigate characteristics of interferometric fringes in the simulation and real scenario separately, and integrate an almost parameter-free unsupervised clustering method and seeding filling or eraser algorithm to propose a hierarchical plug and play method to improve location accuracy. Then, we apply our method to locate single and multiple sources’ interferometric fringes in simulation data. Next, we apply our method to real data taken from the Tianlai radio telescope array. Finally, we compare with unsupervised methods that are state of the art. These results show that our method has robustness in different scenarios and can improve location measurement accuracy effectively.