The MOLLER Experiment Measurement Of Lepton Lepton Elastic Reactions An Ultra-precise Measurement of the Weak Mixing Angle using Møller Scattering

The upgraded 11 GeV CEBAF polarized electron beam presents a compelling opportunity to measure a weak neutral current amplitude to unprecedented precision at Q ! M Z . The result would yield a precise measurement of the weak mixing angle sin θW , a fundamental parameter of the electroweak theory. The experimental goal of δ(sin θW ) ∼ 0.1%, matching the accuracy of the two single best measurements by ee colliders at the Z resonance, would be accomplished by a precise measurement of the parity-violating asymmetry in fixed-target Møller scattering. The quantitative goals, the measurement strategy, and the major parameters of the experimental design in the original proposal remain unchanged, and we will refer to it frequently in this document. The original proposal document can be found at http://hallaweb.jlab.org/12GeV/Moller/moller_final.pdf. After presenting a brief overview of the experiment, we address a few aspects of the experimental design that have seen progress in recent months, both due to dedicated studies as well as due to technical accomplishments in other related projects. We conclude with a projection of the required beam time to achieve the proposed accuracy for the measurement. J. Benesch, P. Brindza, R.D. Carlini, J-P. Chen, E. Chudakov, S. Covrig, C.W. de Jager, A. Deur, D. Gaskell, J. Gomez, D.W. Higinbotham, J. LeRose, D. Mack, R. Michaels, B. Moffit, S. Nanda, G.R. Smith, P. Solvignon, R. Suleiman, B. Wojtsekhowski Jefferson Lab H. Baghdasaryan, G. Cates, D. Crabb, D. Day, M.M. Dalton, C. Hanretty, N. Kalantarians, N. Liyanage, V.V. Nelyubin, B. Norum, K. Paschke, M. Shabestari, J. Singh, A. Tobias, K. Wang, X. Zheng University of Virginia S. Johnston, K.S. Kumar [Contact], J. Mammei, L. Mercado, R. Miskimen, S. Riordan, J. Wexler University of Massachusetts, Amherst J. Birchall, M.T.W. Gericke, W.R. Falk, L. Lee, S.A. Page, W.T.H. van Oers University of Manitoba V. Bellini, A. Giusa, F. Mammoliti, G. Russo, M.L. Sperduto, C.M. Sutera INFN Sezione di Catania and Universita’ di Catania D.S. Armstrong, T.D. Averett, W. Deconinck, J. Katich, J.P. Leckey College of William & Mary K. Grimm, K. Johnston, N. Simicevic, S. Wells Louisiana Tech University L. El Fassi, R. Gilman, G. Kumbartzki, R. Ransome, Rutgers University J. Arrington, K. Hafidi, P.E. Reimer, J. Singh Argonne National Lab P. Cole, D. Dale, T.A. Forest, D. McNulty Idhao State University E. Fuchey, F. Itard, C. Muñoz Camacho LPC Clermont, Université Blaise Pascal J.H. Lee, P.M. King, J. Roche Ohio University E. Cisbani, S. Frullani, F. Garibaldi INFN Gruppo Collegato Sanita’ and Istituto Superiore di Sanita’ R. De Leo, L. Lagamba, S. Marrone INFN, Sezione di Bari and University di Bari F. Meddi, G.M. Urciuoli Dipartimento di Fisica dell’Universita’ la Sapienza and INFN Sezione di Roma R. Holmes, P. Souder Syracuse University G. Franklin, B. Quinn Carnegie Mellon University N. Morgan, M. Pitt Virginia Polytechnic Institute and State University J.A. Dunne, D. Dutta Mississippi State University A.T. Katramatou, G. G. Petratos Kent State University A. Ahmidouch, S. Danagoulian North Carolina A&T State University S. Kowalski, V. Sulkosky MIT P. Decowski Smith College J. Erler Universidad Autónoma de México M.J. Ramsey-Musolf University of Wisconsin, Madison Yu.G. Kolomensky University of California, Berkeley K. A. Aniol California State U.(Los Angeles) C.A. Davis, W.D. Ramsay TRIUMF J.W. Martin University of Winnipeg E. Korkmaz University of Northern British Columbia T. Holmstrom Longwood University S.F. Pate New Mexico State University G. Ron Hebrew University of Jerusalem D.T. Spayde Hendrix College P. Markowitz Florida International University F.R. Wesselmann Xavier University of Louisiana F. Maas Johannes Gutenberg Universitaet Mainz C. Hyde Old Dominion University F. Benmokhtar Christopher Newport University E. Schulte Temple University C. Hyde Old Dominion University M. Capogni Istituto Nazionale di Metrologia delle Radiazioni Ionizzanti ENEA and INFN Gruppo Collegato Sanita’ R. Perrino INFN Sezione di Lecce [email protected]