* Astronomy

Title: CLASH: Mass Distribution in and around MACS J1206.2-0847 from a Full Cluster Lensing Analysis
Authors: Keiichi Umetsu (ASIAA, Taiwan), Elinor Medezinski, Mario Nonino, Julian Merten, Adi Zitrin, Alberto Molino, Claudio Grillo, Mauricio Carrasco, Megan Donahue, Andisheh Mahdavi, Dan Coe, Marc Postman, Anton Koekemoer, Nicole Czakon, Jack Sayers, Tony Mroczkowski, Sunil Golwala, Patrick M. Koch, Kai-Yang Lin, Sandor M. Molnar, Piero Rosati, Italo Balestra, Amata Mercurio, Marco Scodeggio, Andrea Biviano, Timo Anguita, Leopoldo Infante, Gregor Seidel, Irene Sendra, Stephanie Jouvel, Ole Host, Doron Lemze, Tom Broadhurst, Massimo Meneghetti, Leonidas Moustakas, Matthias Bartelmann, Narciso Benitez, Rychard Bouwens, Larry Bradley, Holland Ford, Yolanda Jimenez-Teja, Daniel Kelson, Ofer Lahav, Peter Melchior, John Moustakas, Sara Ogaz, Stella Seitz, Wei Zheng

We derive an accurate mass distribution of the galaxy cluster MACS J1206.2-0847 (z=0.439) from a combined weak-lensing distortion, magnification, and strong-lensing analysis of wide-field Subaru BVRIz' imaging and our recent 16-band Hubble Space Telescope observations taken as part of the Cluster Lensing And Supernova survey with Hubble (CLASH) program. We find good agreement in the regions of overlap between several weak and strong lensing mass reconstructions using a wide variety of modelling methods, ensuring consistency. The Subaru data reveal the presence of a surrounding large scale structure with the major axis running approximately north-west south-east (NW-SE), aligned with the cluster and its brightest galaxy shapes, showing elongation with a ~ 2:1 axis ratio in the plane of the sky. Our full-lensing mass profile exhibits a shallow profile slope dln\Sigma/dlnR~ -1 at cluster outskirts (R>1Mpc/h), whereas the mass distribution excluding the NW-SE excess regions steepens further out, well described by the Navarro-Frenk-White form. Assuming a spherical halo, we obtain a virial mass M_{vir}=(1.1±0.2±0.1) x 10^{15} solar masses/h and a halo concentration c_{vir} = 6.9±1.0±1.2 (~ 5.7 when the central 50kpc/h is excluded), which falls in the range 4< <c> <7 of average c(M,z) predictions for relaxed clusters from recent Lambda cold dark matter simulations. Our full lensing results are found to be in agreement with X-ray mass measurements where the data overlap, and when combined with Chandra gas mass measurements, yield a cumulative gas mass fraction of 13.7^{+4.5}_{-3.0}% at 0.7Mpc/h (~ 1.7r_{2500}), a typical value observed for high mass clusters.

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