Speaker
Description
Electromagnetic polarizabilities are fundamental properties of composite systems such as molecules, atoms, nuclei and hadrons. Polarizabilities measure the 'stiffness' of a system to electromagnetic deformation. Measurements of hadron polarizabilities provide a test of effective field theories, dispersion theories, and lattice calculations. While significant progress has been made in measurements of nucleon polarizabilities, with uncertainties for the proton at the level of 0.4 x 10-4 e fm2, experimental constraints on the charged and neutral pion polarizabilities (CPP and NPP) are much weaker, 2 x 10-4 for the charged pion and no measurement for the neutral pion. The CPP and NPP experiments at GlueX utilize a new technique to measure pion polarizabilities, Primakoff photo-production of charged and neutral pion pairs using linearly polarized 6 GeV photons on a 208Pb target. Details of the experimental setup and preliminary analysis will be presented in the talk. The CPP and NPP experiments are finishing data taking at JLab summer 2022.
| speaker affiliation | University of Massachusetts, Amherst |
|---|
