2015/11/09 by Alexey Guskov, Guskov, Alexey
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #Nuclear Experiment (nucl-ex) #hep-ex #nucl-ex
paper · pdf · doi:10.48550/arxiv.1511.02816
EPS-HEP-2015 proceedings
arxiv created 2015/11/09 · arxiv updated 2015/11/10
The electric (απ) and the magnetic (βπ) polarisabilities are fundamental properties of the pion characterising the rigidity of its internal structure. They have been precisely measured at the COMPASS experiment at CERN with a π- beam of 190~GeV/c assuming απ+βπ=0. Muons of the same momentum were used for controlling of systematic effects. The obtained result απ=-βπ=(2.0± 0.6stat.± 0.7syst.)× 10-4 fm3 is in agreement with the prediction of the Chiral Perturbation Theory.