摘要：We examined the reconstruction of galaxy cluster radial density profiles obtained fromChandraandXMM-NewtonX-ray observations, using high quality data for a sample of twelve objects covering a range of morphologies and redshifts. By comparing the results obtained from the two observatories and by varying key aspects of the analysis procedure, we examined the impact of instrumental effects and of differences in the methodology used in the recovery of the density profiles. We find that the final density profile shape is particularly robust. We adapted the photon weighting vignetting correction method developed forXMM-Newtonfor use withChandradata, and confirm that the resultingChandraprofiles are consistent with those corrected a posteriori for vignetting effects. Profiles obtained from direct deprojection and those derived using parametric models are consistent at the1%level. At radii larger than~6″, the agreement betweenChandraandXMM-Newtonis better than1%, confirming an excellent understanding of theXMM-NewtonPSF. Furthermore, we find no significant energy dependence. The impact of the well-known offset betweenChandraandXMM-Newtongas temperature determinations on the density profiles is found to be negligible. However, we find an overall normalisation offset in density profiles of the order of~2.5%, which is linked to absolute flux cross-calibration issues. As a final result, the weighted ratios ofChandratoXMM-Newtongas masses computed atR2500andR500arer= 1.03 ± 0.01andr= 1.03 ± 0.03, respectively. Our study confirms that the radial density profiles are robustly recovered, and that any differences betweenChandraandXMM-Newtoncan be constrained to the~2.5% level, regardless of the exact data analysis details. These encouraging results open the way for the true combination of X-ray observations of galaxy clusters, fully leveraging the high resolution ofChandraand the high throughput ofXMM-Newton.
关键词：enmethods: data analysisgalaxies: clusters: intracluster mediumX-rays: galaxies: clusters
