Impact parameter study of elastic hadron--proton scattering at 50 and 175 GeV/c. Interim report No. 137. [Differential cross sections, optical model, partial waves]

Technical Report · Thu Apr 01 04:00:00 EST 1976

DOI:https://doi.org/10.2172/7144618· OSTI ID:7144618

Heltsley, B K

In hadron-proton collisions at high energies, the impact profile function measures the range and strength of the strong interaction. It determines the effective size and shape of the hadrons involved, for purposes of both elastic scattering and particle production, but depends solely upon the behavior in t of the elastic differential cross-section. Such an analysis of the reactions ..pi.. +- p, K +- p, and p +- p at incident momenta from 50 to 175 GeV/c is presented using the elastic scattering data recently taken. Two derivations of the profile function are given: the classic optical model and the partial wave treatment. The first stresses the ''grey disc'' interpretations of hadrons; both allow the decomposition of the profile into the elastic and inelastic overlap functions, which represent the probabilities of each of the two processes. A more rigorous procedure yielding essentially the same result involves the imposition of unitarity on the relativistic S-matrix and then requiring angular momentum conservation. Cross section measurements extend to t = -0.8 (GeV/c)/sup 2/; this calculation assumes pure exponential behavior thereafter, and accounts for the possibility of a sharp decrease in its slope at larger t. The real part of the scattering amplitude is neglected. The results display good qualitative agreement with the shadow-diffraction scattering model, and with previous analyses. They indicate distinct differences between meson-baryon and baryon-baryon interactions, and imply that dependence of the cross section on energy derives primarily from a net change in peripheral processes. A test of the quark model and the Lipkin sum rules shows substantial deviation from theoretical expectations.

• Research Organization: Brown Univ., Providence, R.I. (USA). Dept. of Physics
• OSTI ID: 7144618
• Report Number(s): COO-3130TB-221
• Country of Publication: United States
• Language: English

Related Subjects

645204* -- High Energy Physics-- Particle Interactions & Properties-Theoretical-- Strong Interactions & Properties
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ANGULAR MOMENTUM
BARYON-BARYON INTERACTIONS
COMPOSITE MODELS
CONSERVATION LAWS
CROSS SECTIONS
DIAGRAMS
DIFFERENTIAL CROSS SECTIONS
ELASTIC SCATTERING
ENERGY RANGE
EQUATIONS
HADRON-HADRON INTERACTIONS
IMPACT PARAMETER
INTERACTIONS
MATHEMATICAL MODELS
MATRICES
MESON-BARYON INTERACTIONS
OPTICAL MODELS
PARTIAL WAVES
PARTICLE INTERACTIONS
PARTICLE MODELS
PROBABILITY
QUARK MODEL
RELATIVISTIC RANGE
S MATRIX
SCATTERING
SUM RULES
UNITARITY