HST/ACS weak lensing analysis of the galaxy cluster RDCS 1252.9-2927 at z=1.24

Authors :: Lombardi, M.
Rosati, P.
Blakeslee, J. P.
Ettori, S.
Demarco, R.
Ford, H. C.
Illingworth, G. D.
Clampin, M.
Hartig, G. F.
Benitez, N.
Broadhurst, T. J.
Franx, M.
Jee, M. J.
Postman, M.
White, R. L.
Publication Year :: 2005
Publisher :: arXiv, 2005.
Abstract: We present a weak lensing analysis of one of the most distant massive galaxy cluster known, RDCS 1252.9-2927 at z=1.24, using deep images from the Advanced Camera for Survey (ACS) on board the Hubble Space Telescope (HST). By taking advantage of the depth and of the angular resolution of the ACS images, we detect for the first time at z>1 a clear weak lensing signal in both the i (F775W) and z (F850LP) filters. We measure a 5-\sigma signal in the i band and a 3-\sigma signal in the shallower z band image. The two radial mass profiles are found to be in very good agreement with each other, and provide a measurement of the total mass of the cluster inside a 1Mpc radius of M(<br />Comment: 38 pages, ApJ in press. Full resolution images available at http://www.eso.org/~prosati/RDCS1252/Lombardi_etal_accepted.pdf