Measurement of the doubly differential cross section for. pi. /sup -/p. --> pi. /sup +/. pi. /sup -/n near threshold

Thesis/Dissertation · Mon Jan 01 04:00:00 EST 1979

OSTI ID:5195324

Walter, J B

The doubly differential cross sections for the ..pi../sup +/ from the reaction ..pi../sup -/p..--> pi../sup +/..pi../sup -/n were measured at about twenty points for each of five energies between 245 MeV and 356 MeV. The experiment was carried out at the Clinton P. Anderson Meson Physics Facility, where a double focussing magnetic spectrometer detected the ..pi../sup +/ mesons produced in a liquid hydrogen target. The measurements were normalized by comparison with ..pi../sup -/p elastic scattering measured with the same apparatus. These are the first such measurements in this energy range, and have an accuracy between 4.7 and 39%. The integrated reaction cross section was determined at each energy with an accuracy of about 5%. These agree with but are an improvement over previous measurements in this energy range. Comparison of the extrapolated threshold value of the mean square modulus of the matrix element with the soft pion calculations favors the symmetry breaking mechanism of Weinberg (xi = 0). It also demonstrates the futility of attempting to determine the symmetry breaking parameter xi from a single measurement of the integrated reaction cross section.

• Research Organization: Wyoming Univ., Laramie (USA)
• OSTI ID: 5195324
• 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
CROSS SECTIONS
DATA
DIFFERENTIAL CROSS SECTIONS
ELEMENTARY PARTICLES
ENERGY RANGE
EXPERIMENTAL DATA
FERMIONS
HADRON-HADRON INTERACTIONS
HADRONS
INFORMATION
INTEGRAL CROSS SECTIONS
INTERACTIONS
MESON-BARYON INTERACTIONS
MESON-NUCLEON INTERACTIONS
MESONS
MEV RANGE
MEV RANGE 100-1000
NEUTRONS
NUCLEONS
NUMERICAL DATA
PARTICLE INTERACTIONS
PARTICLE PRODUCTION
PION MINUS-PROTON INTERACTIONS
PION-NUCLEON INTERACTIONS
PION-PROTON INTERACTIONS
PIONS
PIONS MINUS
PIONS PLUS
PSEUDOSCALAR MESONS
SYMMETRY BREAKING