Guangzhi He, Shifan Zuo, Jixia Li, Yichao Li, Furen Deng, Shijie Sun, Reza Ansari, Olivier Perdereau, Peter Timbie, Albert Stebbins, Ayodeji Ibitoye, Fengquan Wu, Yougang Wang, Xuelei Chen

The Tianlai Dish Pathfinder Array (TDPA) is a radio interferometer designed to test techniques for 21 cm intensity mapping in the post-reionization universe as a means of measuring large-scale cosmic structure. Using 9 nights of observations targeting the North Celestial Pole (NCP) field, totaling approximately 107 hours of integration time, we analyze data in the frequency range 700-800 MHz (corresponding to redshift $z \sim 0.9$). We do the data format conversion, radio frequency interference (RFI) flagging, calibration, imaging and point source subtraction, and foreground removal via Singular Value Decomposition (SVD). The spherically averaged power spectrum $Δ^2(k)$ is obtained. This work successfully establishes and validates a comprehensive data analysis framework for the TDPA. We identify key improvements including sky model refinement, increased integration time, and pipeline optimization that will enable future detection of the 21 cm signal through auto-correlation and cross-correlation with optical galaxy surveys.