We present a multi-wavelength study of the massive ( M _ { 200 \textrm { c } } \approx 1 - 2 \times 10 ^ { 15 } M _ { \odot } ) galaxy clusters RXC J2248.7 - 4431 , MACS J0416.1 - 2403 , and MACS J1206.2 - 0847 at z \approx 0.4 .
Using the X-ray surface brightness of the clusters from deep Chandra data to model their hot gas , we are able to disentangle this mass term from the diffuse dark matter in our new strong-lensing analysis , with approximately 50 - 100 secure multiple images per cluster , effectively separating the collisional and collisionless mass components of the clusters .
At a radial distance of 10 \% of R _ { 200 \textrm { c } } ( approximately 200 kpc ) , we measure a projected total mass of ( 0.129 \pm 0.001 ) , ( 0.131 \pm 0.001 ) and ( 0.137 \pm 0.001 ) \times M _ { 200 \textrm { c } } , for RXC J2248 , MACS J0416 and MACS J1206 , respectively .
These values are surprisingly similar , considering the large differences in the merging configurations , and , as a consequence , in the mass models of the clusters .
Interestingly , at the same radii , the hot gas over total mass fractions differ substantially , ranging from 0.082 \pm 0.001 to 0.133 \pm 0.001 , reflecting the various dynamical states of the clusters .
Moreover , we do not find a statistically significant offset between the positions of the peak of the diffuse dark matter component and of the BCG in the more complex clusters of the sample .
We extend to this sample of clusters previous findings of a number of massive sub-halos higher than in numerical simulations .
These results highlight the importance of a proper separation of the different mass components to study in detail the properties of dark matter in galaxy clusters .