QCD and strongly coupled gauge theories : challenges and perspectives

We highlight the progress, current status, and open challenges of QCD-driven physics, in theory and in experiment. We discuss how the strong interaction is intimately connected to a broad sweep of physical problems, in settings ranging from astrophysics and cosmology to strongly coupled, complex systems in particle and condensed-matter physics, as well as to searches for physics beyond the Standard Model. We also discuss how success in describing the strong interaction impacts other fields, and, in turn, how such subjects can impact studies of the strong interaction. In the course of the work we offer a perspective on the many research streams which flow into and out of QCD, as well as a vision for future developments.Peer reviewe

The QpWeak experiment - A search for physics beyond the standard model via a measurement of the proton's weak charge

In May 2012, the QpWeak collaboration completed a two year measurement program to determine the weak charge of the proton QpWeak = (1 - 4 sin2θW at the Thomas Jefferson National Accelerator Facility (TJNAF). The experiment was designed to produce a 4. 0 % measurement of the weak charge, via a 2. 5 % measurement of the parity violating asymmetry in the number of elastically scattered 1. 165 GeV electrons from protons, at forward angles. At the proposed precision, the experiment would produce a 0. 3 % measurement of the weak mixing angle at a momentum transfer of Q2 = 0. 026 GeV2, making it the most precise stand alone measurement of the weak mixing angle at low momentum transfer. In combination with other parity measurements, QpWeak will also provide a high precision determination of the weak charges of the up and down quarks. At the proposed precision, a significant deviation from the Standard Model prediction could be a signal of new physics at mass scales up to ≃ 6 TeV, whereas agreement would place new and significant constraints on possible Standard Model extensions at mass scales up to ≃ 2 TeV. This paper provides an overview of the physics and the experiment, as well as a brief look at some preliminary diagnostic and analysis data. © 2013 Springer Science+Business Media Dordrecht.D. Androic ... R. D. Young ... et al