Forecast of Neutrino Cosmology from the CSST Photometric Galaxy
  Clustering and Cosmic Shear Surveys
  China Space Station Telescope (CSST) is a forthcoming powerful Stage IV
space-based optical survey equipment. It is expected to explore a number of
important cosmological problems in extremely high precision. In this work, we
focus on investigating the constraints on neutrino mass and other cosmological
parameters under the model of cold dark matter with a constant equation of
state of dark energy ($w$CDM), using the mock data from the CSST photometric
galaxy clustering and cosmic shear surveys (i.e. 3$\times$2pt). The systematics
from galaxy bias, photometric redshift uncertainties, intrinsic alignment,
shear calibration, baryonic feedback, non-linear, and instrumental effects are
also included in the analysis. We generate the mock data based on the COSMOS
catalog considering the instrumental and observational effects of the CSST, and
make use of the Markov Chain Monte Carlo (MCMC) method to perform the
constraints. Comparing to the results from current similar measurements, we
find that CSST 3$\times$2pt surveys can improve the constraints on the
cosmological parameters by one order of magnitude at least. We can obtain an
upper limit for the sum of neutrino mass $\Sigma m_{\nu} \lesssim 0.36$ (0.56)
eV at 68\% (95\%) confidence level, and $\Sigma m_{\nu} \lesssim 0.23$ (0.29)
eV at 68\% (95\%) confidence level if ignore the baryonic effect, which is
comparable to the {\it Planck} results and much better than the current
photometric surveys. This indicates that the CSST photometric surveys can
provide stringent constraints on the neutrino mass and other cosmological
parameters, and the results also can be further improved by including data from
other kinds of CSST cosmological surveys.
