Measurement and isobar-model analysis of the doubly differential cross section for the. pi. /sup +/ produced in. pi. /sup -/p. -->. pi. /sup +/. pi. /sup -/n

Thesis/Dissertation · Thu Jan 01 04:00:00 EST 1981

OSTI ID:5985851

Manley, D M

The doubly differential cross section (d/sup 2/ sigma/d..cap omega.. dT for ..pi../sup +/ mesons produced in the reaction ..pi../sup -/p ..-->.. ..pi../sup +/..pi../sup -/n was measured at 203, 230, 256, and 358 MeV with a single-arm magnetic spectrometer. A set of five previous measurements at 254, 280, 292, 331, and 356 MeV were reanalyzed with the new measurements. Integrated cross sections were calculated for the combined data set with unprecedented accuracy for this energy range. The chiral-symmetry-breaking parameter was determined to be xi = -0.03 +- 0.26 by extrapolating the mean square modulus of the matrix element with the prediction of soft-pion theory. This value of xi is consistent with zero as required by the Weinberg Lagrangian. Measurements at the three highest energies were compared with the results of an isobar-model analysis of bubble-chamber events by an LBL-SLAC collaboration. After allowing for an overlal normalization difference, the measurements at 331 and 358 MeV were in excellent agreement with the results of their analysis. The measurement at 292 MeV required variation of the PS11(epsilon N) amplitude, as well as the overall normalization, which could be due to the limited number of bubble-chamber events available for the LBL-SLAC analysis at this energy. A partial-wave analysis of the measurements was also carried out with the VPI isobar model.

• Research Organization: Wyoming Univ., Laramie (USA)
• OSTI ID: 5985851
• 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
DATA
DIFFERENTIAL CROSS SECTIONS
ELEMENTARY PARTICLES
ENERGY RANGE
EXPERIMENTAL DATA
FERMIONS
HADRON-HADRON INTERACTIONS
HADRONS
INFORMATION
INTEGRAL CROSS SECTIONS
INTERACTIONS
ISOBAR MODEL
MATHEMATICAL MODELS
MESON-BARYON INTERACTIONS
MESON-NUCLEON INTERACTIONS
MESONS
MEV RANGE
MEV RANGE 100-1000
NEUTRONS
NUCLEONS
NUMERICAL DATA
PARTIAL WAVES
PARTICLE INTERACTIONS
PARTICLE MODELS
PARTICLE PRODUCTION
PION MINUS-PROTON INTERACTIONS
PION-NUCLEON INTERACTIONS
PION-PROTON INTERACTIONS
PIONS
PIONS MINUS
PIONS PLUS
PSEUDOSCALAR MESONS
SYMMETRY
SYMMETRY BREAKING