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Lens magnification by CL0024+1654 in the U and R band

S. Dye·A. N. Taylor·T. R. Greve·O. E. Rognvaldsson·E. van Kampen·P. Jakobsson·V. S. Sigmundsson·E. H. Gudmundsson·J. Hjorth
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Abstract

[ABRIDGED] We estimate the total mass distribution of the galaxy cluster CL0024+1654 from the measured source depletion due to lens magnification in the R band. Within a radius of 0.54Mpc/h, a total projected mass of (8.1+/-3.2)*10^14 M_sol/h (EdS) is measured, which corresponds to a mass- to-light ratio of M/L(B)=470+/-180. We compute the luminosity function of CL0024+1654 in order to estimate contamination of the background source counts from cluster galaxies. Three different magnification-based reconstruction methods are employed using both local and non-local techniques. We have modified the standard single power-law slope number count theory to incorporate a break and applied this to our observations. Fitting analytical magnification profiles of different cluster models to the observed number counts, we find that the cluster is best described either by a NFW model with scale radius r_s=334+/-191 kpc/h and normalisation kappa_s=0.23+/-0.08 or a power-law profile with slope xi=0.61+/-0.11, central surface mass density kappa_0=1.52+/-0.20 and assuming a core radius of r_core=35 kpc/h. The NFW model predicts that the cumulative projected mass contained within a radius R scales as M( 0.15 up to U_AB<=26.4 with 95% confidence.

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S. Dye, A. N. Taylor, T. R. Greve, O. E. Rognvaldsson, E. van Kampen, P. Jakobsson, V. S. Sigmundsson, E. H. Gudmundsson, J. Hjorth. 2002-01-28. Lens magnification by CL0024+1654 in the U and R band. https://doi.org/10.1051/0004-6361%3A20020226

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