摘要
Cross-correlating the data on neutral hydrogen(HⅠ)21 cm intensity mapping with galaxy surveys is an effective method to extract astrophysical and cosmological information.In this work,we investigate the cross-correlation of MeerKAT single-dish mode HⅠintensity mapping and China Space Station Telescope(CSST)spectroscopic galaxy surveys.We simulate a survey area of~300 deg~2 of MeerKAT and CSST surveys at z=0.5 using MultiDark N-body simulation.The PC A algorithm is applied to remove the foregrounds of HⅠintensity mapping,and signal compensation is considered to solve the signal loss problem in HⅠ-galaxy cross power spectrum caused by the foreground removal process.We find that from CSST galaxy auto and MeerKAT-CSST cross power spectra,the constraint accuracy of the parameter productΩ_(HⅠ)b_(HⅠ)r_(HⅠ,g)can reach~1%,which is about one order of magnitude higher than the current results.After performing the full MeerKAT HⅠintensity mapping survey with5000 deg~2 survey area,the accuracy can be enhanced to<0.3%.This implies that the MeerKAT-CSST cross-correlation can be a powerful tool to probe the cosmic HⅠproperty and the evolution of galaxies and the Universe.
基金
the support of 2020SKA0110402,MOST-2018YFE0120800
National Key R&D Program of China No.2022YFF0503404
the National Natural Science Foundation of China(NSFC,Grant Nos.11822305,11773031 and 11633004)
support of the National Natural Science Foundation of China(NSFC,Grant Nos.11473044 and 11973047)
the Chinese Academy of Sciences grants QYZDJ-SSW-SLH017,XDB23040100,XDA15020200
supported by the National Research Foundation of South Africa under Grant Nos.150580,120385 and 120378
NIThe CS program“New Insights into Astrophysics and Cosmology with Theoretical Models confronting Observational Data”
supported by the science research grants from the China Manned Space Project with NO.CMS-CSST-2021-B01 and CMS-CSST-2021-A01。
