C. Gheller et al., CONSTRAINING THE COSMOLOGICAL BARYON DENSITY WITH X-RAY-CLUSTERS, Monthly Notices of the Royal Astronomical Society, 296(1), 1998, pp. 85-99
We study the properties of X-ray galaxy clusters in four cold dark mat
ter models with different baryon fractions Omega(BM) ranging from 5 to
20 per cent. By using an original three-dimensional hydrodynamic code
based on the piecewise parabolic method, we run simulations on a box
with a size of 64 h(-1) Mpc and we identify the clusters by selecting
the peaks in the X-ray luminosity field. We analyse these mock catalog
ues by computing the mass function, the luminosity function, the tempe
rature distribution and the luminosity-temperature relation. By compar
ing the predictions of the different models to a series of recent obse
rvational results, we find that only the models with low baryonic cont
ent agree with the data, while models with larger baryon fraction are
well outside the 1 sigma error bars. In particular, the analysis of th
e luminosity functions, both bolometric and in the energy band [0.5-2]
keV, requires Omega(BM) less than or similar to 0.05 when we fix the
values h = 0.5 and n = 0.8 for the Hubble parameter and the primordial
spectral index, respectively. Moreover we find that, independently of
the cosmological scenario, all the considered quantities have very li
ttle redshift evolution, particularly between z = 0.5 and 0.