Constraints on Dark Energy from the CSST Galaxy Clusters

查看全文 作　　者：Yufei [1,2]Zhang;Mingjing [1,2]Chen;Zhonglue [3,4]Wen;Wenjuan [1,2]Fang 机构地区：[1]CAS Key Laboratory for Research in Galaxies and Cosmology,Department of Astronomy,University of Science and Technology of China,Hefei 230026,China;[2]School of Astronomy and Space Science,University of Science and Technology of China,Hefei 230026,China;[3]National Astronomical Observatories,Chinese Academy of Sciences,Beijing 100101,China;[4]CAS Key Laboratory of FAST,NAOC,Chinese Academy of Sciences,Beijing 100101,China 出　　处：《Research in Astronomy and Astrophysics》索引2023年第23卷第4期,共11页 基　　金：supported by the National Key R&D Program of China grants Nos.2022YFF0503404 and 2021YFC2203102;by the National Natural Science Foundation of China (NSFC,Grant Nos.12173036,11773024,11653002,11421303 and 12073036);by the China Manned Space Project grant No.CMSCSST-2021-B01;by the Fundamental Research Funds for Central Universities Grant Nos.WK3440000004 and WK3440000005;by the CAS Interdisciplinary Innovation Team。 摘　　要：We study the potential of the galaxy cluster sample expected from the Chinese Space Station Telescope(CSST)survey to constrain dark energy properties.By modeling the distribution of observed cluster mass for a given true mass to be log-normal and adopting a selection threshold in the observed mass M_(200m)≥0.836×10^(14)h^(-1)M_(⊙),we find about 4.1×10^(5)clusters in the redshift range 0≤z≤1.5 can be detected by the CSST.We construct the Fisher matrix for the cluster number counts from CSST,and forecast constraints on dark energy parameters for models with constant(w_(0)CDM)and time dependent(w_(0)w_(a)CDM)equation of state.In the self-calibration scheme,the dark energy equation of state parameter w_(0)of the w_(0)CDM model can be constrained toΔw_(0)=0.036.If w_(a)is added as a free parameter,we obtainΔw_(0)=0.077 andΔw_(a)=0.39 for the w_(0)w_(a)CDM model,with a Figure of Merit for(w_(0),w_(a))of 68.99.Should we have perfect knowledge of the observable-mass scaling relation('known SR'scheme),we would obtainΔw_(0)=0.012 for the w_(0)CDM model,andΔw_(0)=0.062 andΔw_(a)=0.24 for the w_(0)w_(a)CDM model.The dark energy Figure of Merit of(w_(0),w_(a))increases to 343.25.This indicates again the importance of calibrating the observable-mass scaling relation for optically selected galaxy clusters.By extending the_(max)imum redshift of the clusters from z_(max)~1.5 to Z_(max)~2,the dark energy Figure of Merit for(w_(0),w_(a))increases to 89.72(self-calibration scheme)and 610.97('known SR'scheme),improved by a factor of~1.30 and~1.78,respectively.We find that the impact of clusters’redshift uncertainty on the dark energy constraints is negligible as long as the redshift error of clusters is smaller than 0.01,achievable by CSST.We also find that the bias in logarithm mass must be calibrated to be 0.30 or better to avoid significant dark energy parameter bias. 关 键 词：(cosmology:)dark energy-galaxies CLUSTERS general-(cosmology:)cosmological parameters