The Local Cluster Substructure Survey ( LoCuSS , Smith et al . )
is a systematic multi-wavelength survey of more than 100 X-ray luminous galaxy clusters in the redshift range 0.14-0.3 selected from the ROSAT All Sky Survey .
We used data on 37 LoCuSS clusters from the XMM-Newton archive to investigate the global scaling relations of galaxy clusters .
The scaling relations based solely on the X-ray data ( S – T , S – Y _ { X } , P – Y _ { X } , M – T , M – Y _ { X } , M – M _ { gas } , M _ { gas } – T , L – T , L – Y _ { X } , and L – M ) obey empirical self-similarity and reveal no additional evolution beyond the large-scale structure growth .
They also reveal up to 17 per cent segregation between all 37 clusters and non-cool core clusters .
Weak lensing mass measurements are also available in the literature for 19 of the clusters with XMM-Newton data .
The average of the weak lensing mass to X-ray based mass ratio is 1.09 \pm 0.08 , setting the limit of the non-thermal pressure support to 9 \pm 8 per cent .
The mean of the weak lensing mass to X-ray based mass ratio of these clusters is \sim 1 , indicating good agreement between X-ray and weak lensing masses for most clusters , although with 31–51 per cent scatter .
The scatter in the mass–observable relations ( M – Y _ { X } , M – M _ { gas } , and M – T ) is smaller using X-ray based masses than using weak lensing masses by a factor of 2 .
With the scaled radius defined by the Y _ { X } profile – r _ { 500 } ^ { Y _ { X } ,X } , r _ { 500 } ^ { Y _ { X } ,wl } , and r _ { 500 } ^ { Y _ { X } ,si } , we obtain lower scatter in the weak lensing mass based mass–observable relations , which means the origin of the scatter is M ^ { wl } and M ^ { X } instead of Y _ { X } .
The normalization of the M – Y _ { X } relation using X-ray mass estimates is lower than the one from simulations by up to 18–24 per cent at 3 \sigma significance .
This agrees with the M – Y _ { X } relation based on weak lensing masses , the normalization of the latter being \sim 20 per cent lower than the one from simulations at \sim 2 \sigma significance .
This difference between observations and simulations is also indicated in the M – M _ { gas } and M – T relations .
Despite the large scatter in the comparison of X-ray to lensing , the agreement between these two completely independent observational methods is an important step towards controlling astrophysical and measurement systematics in cosmological scaling relations .

osmology : observations – Galaxies : clusters : general – X-rays : galaxies : clusters – ( Cosmology : ) dark matter – Gravitational lensing