The XXL Survey . IV. Masstemperature relation of the bright cluster sample
Abstract
Context. The XXL Survey is the largest survey carried out by XMMNewton. Covering an area of 50 deg^{2}, the survey contains ~450 galaxy clusters out to a redshift ~2 and to an Xray flux limit of ~ 5 × 10^{15} erg s^{1} cm^{2}. This paper is part of the first release of XXL results focussed on the bright cluster sample.
Aims: We investigate the scaling relation between weaklensing mass and Xray temperature for the brightest clusters in XXL. The scaling relation discussed in this article is used to estimate the mass of all 100 clusters in XXL100GC.
Methods: Based on a subsample of 38 objects that lie within the intersection of the northern XXL field and the publicly available CFHTLenS shear catalog, we derive the weaklensing mass of each system with careful considerations of the systematics. The clusters lie at 0.1 <z< 0.6 and span a temperature range of T ≃ 15 keV. We combine our sample with an additional 58 clusters from the literature, increasing the range to T ≃ 110 keV. To date, this is the largest sample of clusters with weaklensing mass measurements that has been used to study the masstemperature relation.
Results: The masstemperature relation fit (M ∝ T^{b}) to the XXL clusters returns a slope and intrinsic scatter σ_{lnMT}≃ 0.53; the scatter is dominated by disturbed clusters. The fit to the combined sample of 96 clusters is in tension with selfsimilarity, b = 1.67 ± 0.12 and σ_{lnMT} ≃ 0.41.
Conclusions: Overall our results demonstrate the feasibility of groundbased weaklensing scaling relation studies down to cool systems of ~1 keV temperature and highlight that the current data and samples are a limit to our statistical precision. As such we are unable to determine whether the validity of hydrostatic equilibrium is a function of halo mass. An enlarged sample of cool systems, deeper weaklensing data, and robust modelling of the selection function will help to explore these issues further.
Based on observations obtained with XMMNewton, an ESA sci ence mission with instruments and contributions directly funded by ESA Member States and NASA. Based on observations made with ESO Telescopes at the La Silla Paranal Observatory under programme 089.A0666 and LP191.A0268.The Master catalogue is available at the CDS via anonymous ftp to http://cdsarc.ustrasbg.fr (http://130.79.128.5) or via http://cdsarc.ustrasbg.fr/vizbin/qcat?J/A+A/592/A2
 Publication:

Astronomy and Astrophysics
 Pub Date:
 June 2016
 DOI:
 10.1051/00046361/201526883
 arXiv:
 arXiv:1512.03857
 Bibcode:
 2016A&A...592A...4L
 Keywords:

 gravitational lensing: weak;
 Xrays: galaxies: clusters;
 galaxies: groups: general;
 galaxies: clusters: general;
 Astrophysics  Cosmology and Nongalactic Astrophysics
 EPrint:
 to be published in A&