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Weak lensing analysis of Cl 1358+62 using Hubble Space Telescope observations

H. Hoekstra·M. Franx·K. Kuijken·G. Squires
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Abstract

We report on the detection of weak gravitational lensing of faint, distant background galaxies by Cl 1358+62, a cluster of galaxies at a redshift of z=0.33. The observations were made using the HST. The measured shear is consistent with a velocity dispersion of 780+-50 km/s. The weak lensing mass is slightly lower than dynamical estimates and agrees well with X-ray mass estimates. The mass distribution is elongated similar to the light. The axis ratio of 0.30+-0.15 and position angle of -21+-8 degrees were measured directly from the observed shear and agree very well with a previous strong lensing analysis. We estimate the mass-to-light ratio to be 90+-13 h50 M_sun/L_Vsun. The HST point spread function is highly anisotropic at the edges of the individual chips. This systematically perturbs the shapes of objects and we present a method for applying the appropriate correction.

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H. Hoekstra, M. Franx, K. Kuijken, G. Squires. 1998-04-07. Weak lensing analysis of Cl 1358+62 using Hubble Space Telescope observations. https://doi.org/10.1016/s1387-6473(98)00035-9

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