I am a researcher specializing in radio astronomy and cosmology, with a focus on neutral hydrogen (HI) intensity mapping and large-scale structure surveys. My work involves developing advanced data analysis techniques, including machine learning methods, to extract cosmological signals from radio observations, and I have contributed to several HI cosmology survey projects utilizing the Green Bank Telescope (GBT), Parkes Telescope, MeerKAT, and Five-hundred-meter Aperture Spherical radio Telescope (FAST).Mapping the Large-Scale Structure of the Universe with Neutral HydrogenMy research focuses on utilizing HI in the galaxy as a cosmological tracer to map the large-scale structure of the Universe. Through HI intensity mapping and spectroscopic surveys, I aim to investigate the distribution and evolution of cosmic structures, providing critical insights into the growth of matter fluctuations, the nature of dark energy, and the underlying cosmological model.Advanced Data Analysis Techniques for Radio CosmologyI am actively involved in the development of innovative data processing and analysis methods tailored to modern radio surveys. This includes statistical techniques for foreground mitigation, noise modeling, and the application of machine learning algorithms to enhance signal extraction. These tools are essential for isolating faint cosmological signatures embedded in complex, massive astronomical data.Exploration of the Ultra-Long Wavelength Radio RegimeI am also interested in the scientific opportunities offered by observations in the ultra-long wavelength (ULW) regime, typically below 30 MHz. This largely unexplored frequency band holds the potential to probe the early universe, including the cosmic Dark Ages and the epoch of reionization (EoR). My work in this area involves investigating observational strategies and instrumentation concepts capable of overcoming ionospheric limitations and radio frequency interference.My research aims to enhance our understanding of the Universe's evolution by improving observational techniques and data processing methods in radio astronomyPublicationsSiyuan Zhang, Qi Niu, Yichao Li and Xin Zhang. "Configuration requirements for 21-cm forest background quasar searches with Moon-based interferometer." Chinese Physics C. DOI: 10.1088/1674-1137/ade957.Jiaxin Wang, Yichao Li, Hengxing Pan, Furen Deng, Diyang Liu, Wenxiu Yang, Wenkai Hu, Yougang Wang, Xin Zhang, and Xuelei Chen. "FAST Drift Scan Survey for HI Intensity Mapping: Simulation of Bayesian-stacking-based HI Mass Function Estimation." The Astrophysical Journal. DOI: 10.3847/1538-4357/adf10c.Li-Yang Gao, Leon V. E. Koopmans, Florent G. Mertens, Satyapan Munshi, Yichao Li, Stefanie A. Brackenhoff, Emilio Ceccotti, J. Kariuki Chege, Anshuman Acharya, Raghunath Ghara, Sambit K. Giri, Ilian T. Iliev, Garrelt Mellema, and Xin Zhang. "Extracting the Epoch of Reionization Signal with 3D U-Net Neural Networks Using a Data-driven Systematic Effect Model." The Astrophysical Journal. DOI: 10.3847/1538-4357/ade2dc.Wenxiu Yang, Yitian Sun, Yougang Wang, Katelin Schutz, Yichao Li, Calvin Leung, Wenkai Hu, Shuanghao Shu, Kiyoshi Masui, and Xuelei Chen. "Searching for Axion Dark Matter Gegenschein of the Vela Supernova Remnant with FAST." The Astrophysical Journal. DOI: 10.3847/1538-4357/adde48.Wenxiu Yang, Laura Wolz, Yichao Li, Wenkai Hu, Steven Cunnington, Keith Grainge, Furen Deng, Shifan Zuo, Shuanghao Shu, Xinyang Zhao, Di Li, Zheng Zheng, Marko Krco, Yinghui Zheng, Linjing Feng, Pei Zuo, Hao Chen, Xue-Jian Jiang, Chen Wang, Pei Wang, Chen-Chen Miao, Yougang Wang, and Xuelei Chen. 2025. "CRAFTS for HI Cosmology. I. Data Processing Pipeline and Validation Tests." The Astrophysical Journal Supplement Series. DOI: 10.3847/1538-4365/adde4a.Guang-Chen Sun, Yichao Li, Furen Deng, Yanping Cong, Fangxia An, Jiajun Zhang, Yougang Wang, Xin Zhang, Xuelei Chen. 2025. "A Multimechanism Hybrid Model of Peaked-spectrum Radio Sources." The Astrophysical Journal. https://do.org/10.3847/1538-4357/adcd75.Diyang Liu, Yichao Li, Denis Tramonte, Furen Deng, Jiaxin Wang, Yougang Wang, Xin Zhang, Xuelei Chen. 2025. "FAST Drift-scan Survey for HI Intensity Mapping: Simulation oZhenglong Li, Diyang Liu, Chengliang Xu, Yichao Li, and Xin Zhang. 2025. "Exploring HI Galaxy Redshift Survey Strategies for the FAST Core Array Interferometry." Research in Astronomy and Astrophysics. https://doi.org/10.1088/1674-4527/adce90.Xinyang Zhao, Yichao Li, Wenxiu Yang, Furen Deng, Yougang Wang, Fengquan Wu, Xin Wang, Xiaohui Sun, Xin Zhang, and Xuelei Chen. 2025. "FAST Drift Scan Survey for HI Intensity Mapping. II. Stacking-Based Beam Construction of the 19-Feed Array at 1.4 GHz." The Astronomical Journal 169 (5): 265. https://doi.org/10.3847/1538-3881/adc2fd.Qi Niu, Yichao Li, Yidong Xu, Hong Guo, and Xin Zhang. 2025. "Prospects for Observing High-Redshift Radio-Loud Quasars in the SKA Era: Paving the Way for 21 Cm Forest Observations." The Astrophysical Journal 978 (2): 145. https://doi.org/10.3847/1538-4357/ad9b97.Jun-Da Pan, Peng-Ju Wu, Guo-Hong Du, Yichao Li, and Xin Zhang. 2025. "Prospects for Cosmological Research with the FAST Array: 21-Cm Intensity Mapping Survey Observation Strategies." Journal of Cosmology and Astroparticle Physics 2025 (01): 080. https://doi.org/10.1088/1475-7516/2025/01/080.Guang-Chen Sun, Qiao Wang, Shude Mao, Yichao Li, Richard J. Long, Ping-Jie Ding, Yougang Wang, Xin Zhang, and Xuelei Chen. 2025. "Dynamical Models of the Milky Way in Action Space with LAMOST DR8 and Gaia EDR3." The Astrophysical Journal 982 (1): 37. https://doi.org/10.3847/1538-4357/adb57e.Wan-Peng Sun, Ji-Guo Zhang, Yichao Li, Wan-Ting Hou, Fu-Wen Zhang, Jing-Fei Zhang, and Xin Zhang. 2025. "Exploring the Key Features of Repeating Fast Radio Bursts with Machine Learning." The Astrophysical Journal980 (2): 185. https://doi.org/10.3847/1538-4357/adad6a.Wenkai Hu, Yougang Wang, Yichao Li, Wenxiu Yang, Yidong Xu, Fengquan Wu, Ue-Li Pen, et al. 2025. "The FAST HI 21 Cm Absorption Blind Survey. II. Statistical Exploration for Associated and Intervening Systems." The Astrophysical Journal Supplement Series 277 (1): 25. https://doi.org/10.3847/1538-4365/adb0c0.Ayodeji Ibitoye, Furen Deng, Yichao Li, Yin-Zhe Ma, Yan Gong, and Xuelei Chen. 2025. "H i Intensity Mapping Cross-Correlation with Thermal Sunyaev-Zel'dovich Fluctuations: Forecasted Cosmological Parameter Estimation for FAST and Planck." The Astrophysical Journal 978 (2): 159. https://doi.org/10.3847/1538-4357/ad91a4.Yichao Li, Yougang Wang, Furen Deng, Wenxiu Yang, Wenkai Hu, Diyang Liu, Xinyang Zhao, et al. 2023. "FAST Drift Scan Survey for Hi Intensity Mapping: I. Preliminary Data Analysis." The Astrophysical Journal 954 (2): 139. https://doi.org/10.3847/1538-4357/ace896.Ji-Guo Zhang, Yichao Li, Jia-Ming Zou, Ze-Wei Zhao, Jing-Fei Zhang, and Xin Zhang. 2024. "Fast Radio Burst Energy Function in the Presence of DMhost Variation." Universe 10 (5): 207. https://doi.org/10.3390/universe10050207.Li-Yang Gau, Yichao Li, Shulei Ni, and Xin Zhang. 2023. "Eliminating Polarization Leakage Effect for Neutral Hydrogen Intensity Mapping with Deep Learning." Monthly Notices of the Royal Astronomical Society 525 (4): 5278-90. https://doi.org/10.1093/mnras/stad2646.Wenkai Hu, Yougang Wang, Yichao Li, Yidong Xu, Wenxiu Yang, Guilaine Lagache, Ue-Li Pen, et al. 2023. "Detections of 21 Cm Absorption with a Blind FAST Survey At z 0.09." Astronomy & Astrophysics 675 (June):A40. https://doi.org/10.1051/0004-6361/202245549.Melis O Irfan, Yichao Li, Mario G Santos, Philip Bull, Junhua Gu, Steven Cunnington, Keith Grainge, and Jingying Wang. 2023. "Mitigating the Effect of 1/f Noise on the Detection of the HI Intensity Mapping Power Spectrum from Single-Dish Measurements." Monthly Notices of the Royal Astronomical Society 527 (3): 4717-29. https://doi.org/10.1093/mnras/stad3457.Ruxi Liang, Furen Deng, Zepei Yang, Chunming Li, Feiyu Zhao, Botao Yang, Shuanghao Shu, et al. 2023. "Detecting H i Galaxies with Deep Neural Networks in the Presence of Radio Frequency Interference." Research in Astronomy and Astrophysics 23 (11): 115006. https://doi.org/10.1088/1674-4527/acd0ed.Ming Zhang, Yichao Li, Jing-Fei Zhang, and Xin Zhang. 2023. "HI Intensity Mapping with MeerKAT: Forecast for Delay Power Spectrum Measurement Using Interferometer Mode." Monthly Notices of the Royal Astronomical Society524 (2): 2420-30. https://doi.org/10.1093/mnras/stad2033.Shulei Ni, Yichao Li, Li-Yang Gao, and Xin Zhang. 2022. "Eliminating Primary Beam Effect in Foreground Subtraction of Neutral Hydrogen Intensity Mapping Survey with Deep Learning." The Astrophysical Journal 934 (1): 83. https://doi.org/10.3847/1538-4357/ac7a34.Jingying Wang, Mario G. Santos, Philip Bull, Keith Grainge, Steven Cunnington, Jose Fonseca, Melis O. Irfan, et al. 2021. "HI Intensity Mapping with MeerKAT: Calibration Pipeline for Multidish Autocorrelation Observations." Monthly Notices of the Royal Astronomical Society 505 (3): 3698-3721. https://doi.org/10.1093/mnras/stab1365.S. Zuo, J. Li, Y. Li, D. Santanu, A. Stebbins, K. W. Masui, R. Shaw, J. Zhang, F. Wu, and X. Chen. 2021. "Data Processing Pipeline for Tianlai Experiment." Astronomy and Computing 34 (January):100439. https://doi.org/10.1016/j.ascom.2020.100439.Laura Wolz, Alkistis Pourtsidou, Kiyoshi W Masui, Tzu-Ching Chang, Julian E Bautista, Eva-Maria Muller, Santiago Avila, et al. 2021. "HI Constraints from the Cross-Correlation of eBOSS Galaxies and Green Bank Telescope Intensity Maps." Monthly Notices of the Royal Astronomical Society 510 (3): 3495-3511. https://doi.org/10.1093/mnras/stab3621.Yichao Li, Mario G. Santos, Keith Grainge, Stuart Harper, and Jingying Wang. 2020. "HI Intensity Mapping with MeerKAT: 1/f Noise Analysis." Monthly Notices of the Royal Astronomical Society 501 (3): 4344-58. https://doi.org/10.1093/mnras/staa3856.Yi-Chao Li, Yin-Zhe Ma, Mathieu Remazeilles, and Kavilan Moodley. 2018. "Measurement of the Pairwise Kinematic Sunyaev-Zeldovich Effect with Planck and BOSS Data." Physical Review D 97 (2). https://doi.org/10.1103/physrevd.97.023514.C J Anderson, N J Luciw, Y -C Li, C Y Kuo, J Yadav, K W Masui, T-C Chang, et al. 2018. "Low-Amplitude Clustering in Low-Redshift 21-Cm Intensity Maps Cross-Correlated with 2dF Galaxy Densities." Monthly Notices of the Royal Astronomical Society 476 (3): 3382-92. https://doi.org/10.1093/mnras/sty346.Yi-Chao Li, and Yin-Zhe Ma. 2017. "Constraints on Primordial Non-Gaussianity from Future Hi Intensity Mapping Experiments." Physical Review D 96 (6). https://doi.org/10.1103/physrevd.96.063525.Yi-Chao Li, Feng-Quan Wu, and Xuelei Chen. 2013. "Constraints on the Brans-Dicke Gravity Theory with the Planck Data." Physical Review D 88 (8). https://doi.org/10.1103/physrevd.88.084053.Yi-Chao Li, Feng-Quan Wu, You-Jun Lu, and Xue-Lei Chen. 2014. "Reducing the Tension between the BICEP2 and the Planck Measurements: A Complete Exploration of the Parameter Space." Physics Letters B 738 (November):206-12. https://doi.org/10.1016/j.physletb.2014.09.053.E. R. Switzer, K. W. Masui, K. Bandura, L.-M. Calin, T.-C. Chang, X.-L. Chen, Y.-C. Li, et al. 2013. "Determination of z ~ 0.8 Neutral Hydrogen Fluctuations Using the 21 Cm Intensity Mapping Autocorrelation." Monthly Notices of the Royal Astronomical Society: Letters 434 (1): L46-50. https://doi.org/10.1093/mnrasl/slt074.K. W. Masui, E. R. Switzer, N. Banavar, K. Bandura, C. Blake, L.-M. Calin, T.-C. Chang, et al. 2013. "MEASUREMENT OF 21 Cm BRIGHTNESS FLUCTUATIONS AT z ~ 0.8 IN CROSS-CORRELATION." The Astrophysical Journal 763 (1): L20. https://doi.org/10.1088/2041-8205/763/1/l20.