While clusters of galaxies are regarded as one of the most important cosmological probes , the conventional spherical modeling of the intracluster medium ( ICM ) and the dark matter ( DM ) , and the assumption of strict hydrostatic equilibrium ( i.e. , the equilibrium gas pressure is provided entirely by thermal pressure ) are very approximate at best .
Extending our previous works , we developed further a method to reconstruct for the first time the full three-dimensional structure ( triaxial shape and principal axis orientation ) of both dark matter and intracluster ( IC ) gas , and the level of non-thermal pressure of the IC gas .
We outline an application of our method to the galaxy cluster Abell 383 , taken as part of the CLASH multi-cycle treasury program , presenting results of a joint analysis of X-ray and strong lensing measurements .
We find that the intermediate-major and minor-major axis ratios of the DM are 0.71 \pm 0.10 and 0.55 \pm 0.06 , respectively , and the major axis of the DM halo is inclined with respect to the line of sight of 21.1 \pm 10.1 deg .
The level of non-thermal pressure has been evaluated to be about 10 \% of the total energy budget .
We discuss the implications of our method for the viability of the CDM scenario , focusing on the concentration parameter C and the inner slope of the DM \gamma , since the cuspiness of dark-matter density profiles in the central regions is one of the critical tests of the cold dark matter ( CDM ) paradigm for structure formation : we measure \gamma = 1.02 \pm 0.06 on scales down to 25 Kpc , and C = 4.76 \pm 0.51 , values which are close to the predictions of the standard model , and providing further evidences that support the CDM scenario .
Our method allows us to recover the three-dimensional physical properties of clusters in a bias-free way , overcoming the limitations of the standard spherical modelling and enhancing the use of clusters as more precise cosmological probes .