Charge symmetry breaking in the neutron proton system

Technical Report · Sat Dec 01 04:00:00 EST 1979

DOI:https://doi.org/10.2172/5483893· OSTI ID:5483893

Cheung, C Y; Henley, E M; Miller, G A

Two consequences of charge symmetry breaking (CSB) in the n-p system are examined. In n-p elastic scattering, CSB nuclear forces cause a difference between the polarizations of the neutron and the proton scattered in opposite directions in the center of mass system. The expected differences in polarizations due to one boson exchanges, particularly a photon exchange, isospin mixed mesons, and a pion (with the n-p mass difference taken into account), are computed. The calculated polarization difference is typically of the order of several tenths of a percent. In np ..-->.. d..pi../sup 0/, the CSB of nuclear forces can be tested by measuring the asymmetry of the angular distribution of deuterons about 90/sup 0/ in the center of mass frame. The expected asymmetry is calculated for one boson exchange CSB mechanisms, as in the elastic scattering. The asymmetry caused by the mixed n-..pi../sup 0/ exchange is dominant, but all of the mechanisms contribute asymmetries with similar angular dependences. The maximum assymmetry is about 0.8% at /sup 0/; the average is about 0.2%.

• Research Organization: Washington Univ., Seattle (USA). Dept. of Physics
• DOE Contract Number: EY-76-C-06-1388
• OSTI ID: 5483893
• Report Number(s): DOE/ER/01388-806; RLO-1388-806
• Country of Publication: United States
• Language: English

Related Subjects

645301* -- High Energy Physics-- Particle Invariance Principles & Symmetries-- General-- (-1987)
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ANGULAR DISTRIBUTION
ASYMMETRY
BARYON-BARYON INTERACTIONS
DISTRIBUTION
ELASTIC SCATTERING
HADRON-HADRON INTERACTIONS
INTERACTIONS
NUCLEON-NUCLEON INTERACTIONS
PARTICLE INTERACTIONS
POLARIZATION
PROTON-NEUTRON INTERACTIONS
PROTON-NUCLEON INTERACTIONS
SCATTERING
SYMMETRY BREAKING