2011

The Proton size anomaly

by Prof. Wai Yee Keung (University o Illinois)

Pacific/Honolulu
417 (Watanabe Hall)

417

Watanabe Hall

Description
SPECIAL HIGH ENERGY PHYSICS SEMINAR A measurement of the Lamb shift in muonic hydrogen yields a charge radius of the proton that is smaller than the CODATA value by about 5 standard deviations. We explore the possibility that new scalar, pseudoscalar, vector, and tensor flavor-conserving nonuniversal interactions may be responsible for the discrepancy. We consider exotic particles that among leptons, couple preferentially to muons, and mediate an attractive nucleon-muon interaction. We find that the many constraints from low energy data disfavor new spin-0, spin-1 and spin-2 particles as an explanation. In charge: John Learned