Publication Date:
2014-08-10
Description:
We present the first scaling relation between weak-lensing galaxy cluster mass, M WL , and near-infrared luminosity, L K . Our results are based on 17 clusters observed with wide-field instruments on Subaru, the United Kingdom Infrared Telescope, the Mayall Telescope, and the MMT. We concentrate on the relation between projected 2D weak-lensing mass and spectroscopically confirmed luminosity within 1 Mpc, modelled as $M_{\rm WL} \propto L_{K}^b$ , obtaining a power-law slope of $b=0.83^{+0.27}_{-0.24}$ and an intrinsic scatter of $\sigma _{lnM_{\rm WL}|L_{K}}=10^{+8}_{-5}$ per cent. Intrinsic scatter of ~10 per cent is a consistent feature of our results regardless of how we modify our approach to measuring the relationship between mass and light. For example, deprojecting the mass and measuring both quantities within r 500 , that is itself obtained from the lensing analysis, yields $\sigma _{lnM_{\rm WL}|L_{K}}=10^{+7}_{-5}$ per cent and $b=0.97^{+0.17}_{-0.17}$ . We also find that selecting members based on their ( J – K ) colours instead of spectroscopic redshifts neither increases the scatter nor modifies the slope. Overall our results indicate that near-infrared luminosity measured on scales comparable with r 500 (typically 1 Mpc for our sample) is a low scatter and relatively inexpensive proxy for weak-lensing mass. Near-infrared luminosity may therefore be a useful mass proxy for cluster cosmology experiments.
Print ISSN:
0035-8711
Electronic ISSN:
1365-2966
Topics:
Physics
Permalink