Measurement of. pi. /sup -/p. -->. pi. /sup -/. pi. /sup +/n near threshold and chiral-symmetry breaking

Journal Article · Sun Jan 13 23:00:00 EST 1980 · Phys. Rev. Lett.; (United States)

DOI:https://doi.org/10.1103/PhysRevLett.44.62· OSTI ID:5554864

Bjork, C W; Jones, S E; King, T R; Manley, D M; Oyer, A T; Rebka, Jr, G A; Walter, J B; Carawon, R; Gram, P A.M.; Shively, F T; Bordner, C A; Lomon, E L

d/sup 2/sigma/d..cap omega..dT for ..pi../sup +/ mesons produced in ..pi../sup -/p ..-->.. ..pi../sup -/..pi../sup +/n was measured at seven incident energies between 203 and 357 MeV and the integrated reaction cross section was calculated. The matrix element, when extrapolated to threshold and compared with soft-pion calculations, determined the chiral-symmetry-breaking parameter xi=0.05 +- 0.26, which is consistent with the Weinberg Lagrangian. The large hard-pion contributions at 203 MeV demonstrated the absolute necessity for comparing at threshold.

• Research Organization: Department of Physics, University of Wyoming, Laramie, Wyoming 82071
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 5554864
• Journal Information: Phys. Rev. Lett.; (United States), Journal Name: Phys. Rev. Lett.; (United States) Vol. 44:2; ISSN PRLTA
• Country of Publication: United States
• Language: English

Related Subjects

645104* -- High Energy Physics-- Particle Interactions & Properties-Experimental-- Strong Meson-Induced Interactions-- (-1987)
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BARYONS
BOSONS
CHIRAL SYMMETRY
CROSS SECTIONS
DIFFERENTIAL CROSS SECTIONS
ELEMENTARY PARTICLES
ENERGY DEPENDENCE
ENERGY RANGE
FERMIONS
FUNCTIONS
HADRON-HADRON INTERACTIONS
HADRONS
INTEGRAL CROSS SECTIONS
INTERACTIONS
LAGRANGIAN FUNCTION
MESON-BARYON INTERACTIONS
MESON-NUCLEON INTERACTIONS
MESONS
MEV RANGE
MEV RANGE 100-1000
NEUTRONS
NUCLEONS
PARTICLE INTERACTIONS
PION MINUS-PROTON INTERACTIONS
PION-NUCLEON INTERACTIONS
PION-PROTON INTERACTIONS
PIONS
PIONS MINUS
PIONS PLUS
PSEUDOSCALAR MESONS
SYMMETRY
SYMMETRY BREAKING