The Partial Wave Analysis (PWA) Workshops, held in alternating years since 2005, bring together the world's experts in a forum recognized internationally for its singular contributions to the fundamental understanding of the most basic building blocks of matter, the neutron and proton constituents of the atomic nucleus. This year's PWA Workshop will be held at the Foggy Bottom Campus of The George Washington University under the auspices of the Columbian College of Arts and Sciences' Center for Nuclear Studies (CNS), which has been chartered since November of 1990 and is universally recognized as an academic leader in the field of the physics of the atomic nucleus. Currently, activity is very high in fundamental and precision nucleon physics. Many recent developments in the field have signaled a reinvigorated interest in and support for the PWA program at the national level, which has been led by the Data Analysis Center (DAC) housed in the CNS since 1998. These developments include the construction of Jefferson Laboratory's 12-GeV Upgrade, which represents substantial commitment at the federal level for equipment and infrastructure supporting the precision nucleon physics program. The nucleon physics program at Jefferson Laboratory is part of an international effort in precision experimental nuclear physics including efforts in Europe and Japan. A wealth of precision data is forthcoming from laboratories both in the United States and international institutions. These new experimental physics efforts have ushered in a renaissance in theoretical and analytical research.
Of broader impact, this year's PWA Workshop will bring specialists and experts together who are presently involved in the analysis of existing and forthcoming experiments on nucleon and hadron physics. Workshop attendees will include students, postdoctoral researchers, and both younger and more experienced faculty and researchers. We will focus on time-sensitive and critical issues addressed to the success of precision nucleon physics experimental programs. Substantial support from Jefferson Laboratory indicates the recognition of the importance of PWA and the work of the DAC and CNS to the success of the program. Beside techniques to be exchanged an important issue is the planning of future experiments to ensure the success of the program.
Main Topics: -PWA, unitarity, and model independence, -Phenomenological analyses: SAID, MAID, EBAC, etc, -Coupled-channels approaches, Isobar and dynamical models, -Status of experiments: piN, electromagnetic pion production, -Nucleon resonances in quark models and lattice QCD, -Dynamically generated resonances, -Bare versus dressed resonance poles, -Effective field theories and chiral corrections. The aim of the Workshop was threefold: First, we got experts together who are presently involved in the partial wave analyses (PWA) of piN scattering and electromagnetic pion production. We focused on critical and sensitive issues addressed to the PWA and coupled channel technologies to determine baryons and their properties. Besides the techniques to be exchanged, an important question was to determine which further experiments are needed to be done, in order to get precise and convergent results for partial waves. Second, we continued and extended the discussion on the interpretation of resonance poles started at BRAG2007 and continued at Trento2009. We had all opinions formulated, expressed, presented in a checkable and reproducible form, and widely discussed. At this point, we also discussed the mechanism of dynamically generated nucleon resonances as an alternative to genuine resonances, typically described within quark models. Third, we discussed recent developments in Effective Field Theory and Lattice QCD to describe the structure and decay of non-strange nucleon resonances. The most prominent candidates are the N(1440) and the N(1535) and their couplings to the pion and photon fields. Training and Development:Discussions in the sessions of the workshop and outside meetings with the world leaders in the field had a great benefit to the graduate students and young professionals attended the meeting. Several post-docs and graduate students gave talks and several GWU graduate students attended Workshop. Internet Dissemination:http://gwdac.phys.gwu.edu/pwa2011/PWAhome.htm All our sponsors are listed athttp://gwdac.phys.gwu.edu/pwa2011/PWAhome.htm Contributions within Discipline: First, we got world experts together who are presently involved in the PWA of piN scattering and electromagnetic pion production. We focused on critical and sensitive issues addressed to the PWA and coupled channel technologies to determine baryons and their properties. Besides the techniques to be exchanged, an important question was to determine which further experiments are needed to be done, in order to get precise and convergent results for partial waves. Second, we continued and extended the discussion on the interpretation of resonance poles started at BRAG2007 and continued at Trento2009. We had all opinions formulated, expressed, presented in a checkable and reproducible form, and widely discussed. At this point, we also discussed the mechanism of dynamically generated nucleon resonances as an alternative to genuine resonances, typically described within quark models. Third, we discussed recent developments in Effective Field Theory and Lattice QCD to describe the structure and decay of non-strange nucleon resonances. The most prominent candidates are the N(1440) and the N(1535) and their couplings to the pion and photon fields. Contributions to Other Disciplines:Multidisciplinary results of the Workshop are applying for different disciplines. Workshop participants discussed, in particular, modern technologies to fit large sets of data, extract baryon and meson resonances and determine their properties. It is applicable to the low-energy neutron and ion physics. These results can contribute to the advance undergraduate and graduate classes as theoretical nuclear physics, computational physics, mathematical methods oftheoretical physics, and QCD lattice. Contributions to Education and Human Resources:Discussions in the sessions of the workshop and outside meetings with the world leaders in the field had a great benefit to the graduate students and young professionals attended the meeting.
