[Theory-seminars] Seminar Reminder: TODAY at 2pm Room F113: Aron Bernstein

[Cesar Fernandez-Ramirez]

Experimental Tests of  QCD Symmetries with Pions : Entering a New Era
A.M. Bernstein
MIT

We are entering a new era in which we can test confinement scale QCD in some well chosen reactions such as  pi-pi and pi-N  scattering, pion properties, and electromagnetic pion production from the nucleon. Based on the spontaneous breaking of chiral symmetry, chiral perturbation theory (ChPT) is believed to approximate confinement scale QCD as demonstrated by increasingly accurate  lattice calculations, particularly in pi-pi scattering. Following a brief  review of this field, emphasis will be given to recent, Increasingly accurate, experiments in electromagnetic pion production experiments from the proton performed at Mainz and JLab; these test ChPT calculations and their energy region of validity. The connection between electromagnetic  pion production, pi-N scattering, and quark mass effects will be presented. 

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César Fernández-Ramírez

Theory Center -- Jefferson Lab
12000 Jefferson Ave., Newport News, VA 23606, USA

Phone: (+1) 757-269-7844
Fax: (+1) 757-269-7002
E-mail: cesar at jlab.org