The Astrophysical Journal, 757:22 (19pp), 2012 September 20 doi:10.1088/0004-637X/757/1/22 C 2012. The American Astronomical Society. All rights reserved. Printed in the U.S.A. CLASH: PRECISE NEW CONSTRAINTS ON THE MASS PROFILE OF THE GALAXY CLUSTER A2261 Dan Coe1, Keiichi Umetsu2, Adi Zitrin3, Megan Donahue4, Elinor Medezinski5, Marc Postman1, Mauricio Carrasco6,7, Timo Anguita6,8, Margaret J. Geller9, Kenneth J. Rines9,10, Antonaldo Diaferio11,12, Michael J. Kurtz9, Larry Bradley1, Anton Koekemoer1, Wei Zheng5, Mario Nonino13, Alberto Molino14, Andisheh Mahdavi15, Doron Lemze5, Leopoldo Infante6, Sara Ogaz1, Peter Melchior16,OleHost17, Holland Ford5, Claudio Grillo18, Piero Rosati7, Yolanda Jimenez-Teja´ 14, John Moustakas19, Tom Broadhurst20,21, Begona˜ Ascaso14, Ofer Lahav17, Matthias Bartelmann3, Narciso Ben´ıtez14, Rychard Bouwens22, Or Graur23, Genevieve Graves24, Saurabh Jha25, Stephanie Jouvel17, Daniel Kelson26, Leonidas Moustakas27, Dan Maoz23, Massimo Meneghetti28, Julian Merten27, Adam Riess1,5, Steve Rodney5, and Stella Seitz29 1 Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA;
[email protected] 2 Institute of Astronomy and Astrophysics, Academia Sinica, Taipei, Taiwan 3 Institut fur¨ Theoretische Astrophysik, Zentrum fur¨ Astronomie der Universitat¨ Heidelberg, Heidelberg, Germany 4 Department of Physics and Astronomy, Michigan State University, East Lansing, MI, USA 5 Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD, USA 6 Department of Astronomy and Astrophysics,