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∼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 Δ2(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.
@article{arxiv.2604.12200,
title = {21 cm Power Spectrum Analysis of North Celestial Pole Observations with the Tianlai Dish Pathfinder Array},
author = {Guangzhi He and Shifan Zuo and Jixia Li and Yichao Li and Furen Deng and Shijie Sun and Reza Ansari and Olivier Perdereau and Peter Timbie and Albert Stebbins and Ayodeji Ibitoye and Fengquan Wu and Yougang Wang and Xuelei Chen},
journal= {arXiv preprint arXiv:2604.12200},
year = {2026}
}