Strangeness exchange in antiproton-proton scattering

Journal Article · Wed Apr 01 04:00:00 EST 1992 · Physical Review, D (Particles Fields); (United States)

DOI:https://doi.org/10.1103/PhysRevD.45.2288· OSTI ID:7235410

Timmermans, R G.E.; Rijken, T A; de Swart, J J ^[1]

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1. Institute for Theoretical Physics, University of Nijmegen, Nijmegen (Netherlands)

A model is presented for the production of antihyperon-hyperon pairs in antiproton-proton scattering in the energy region below 2.0 GeV/{ital c} antiproton laboratory momentum accessible at CERN's Low Energy Antiproton Ring. An antibaryon-baryon potential is constructed from the Nijmegen soft-core one-boson-exchange nucleon-nucleon and hyperon-nucleon potential. Using this potential as an intermediate- and long-range interaction the multichannel Schroedinger equation is solved with a complex boundary condition at {ital r}={ital b}=1.2 fm. The model is applied to the elastic {ital {bar p}p}{r arrow}{ital {bar p}p} scattering data, cross sections, and asymmetries at intermediate energies around 1.5 GeV/{ital c} antiproton momentum. Next we compare it to the full set of data, cross sections, polarizations, and spin correlations on the strangeness-exchange reaction {ital {bar p}p}{r arrow}{bar {Lambda}}{Lambda} which has its threshold at momentum 1435 MeV/{ital c}. Excellent results are obtained. Fitting 157 observables at 6 different energies we reach {chi}{sub min}{sup 2}=180.6, corresponding to {chi}{sup 2}/data = 1.15. The results demonstrate the dominance of the strangeness-changing tensor force due to the combined exchange of the {ital K}(494) and {ital K}{sup *}(892) mesons. The method of calculation is similar to the one employed in the Nijmegen partial-wave analyses of low-energy proton-proton and neutron-proton scattering data. In the same manner we perform a model-independent'' partial-wave analysis of the reaction {ital {bar p}p}{r arrow}{bar {Lambda}}{Lambda} close to threshold. The {ital S}-matrix elements are presented.

• OSTI ID: 7235410
• Journal Information: Physical Review, D (Particles Fields); (United States), Journal Name: Physical Review, D (Particles Fields); (United States) Vol. 45:7; ISSN PRVDA; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

662130 -- General Theory of Particles & Fields-- S-Matrix Theory
Relativistic Scattering Theory-- (1992-)
662240 -- Models for Strong Interactions-- (1992-)
662340* -- Hadron Interactions-- (1992-)
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ANGULAR MOMENTUM
ANTIBARYONS
ANTIHYPERONS
ANTILAMBDA PARTICLES
ANTIMATTER
ANTIPARTICLES
BARYON-BARYON INTERACTIONS
BARYONS
BOSON-EXCHANGE MODELS
BOSONS
BOUNDARY CONDITIONS
BUBBLE CHAMBERS
COUPLING CONSTANTS
CROSS SECTIONS
DIFFERENTIAL EQUATIONS
ELEMENTARY PARTICLES
EQUATIONS
FERMIONS
GAS TRACK DETECTORS
HADRON-HADRON INTERACTIONS
HADRONS
HYPERONS
INTERACTIONS
K -892 MESONS
LAMBDA BARYONS
LAMBDA PARTICLES
LIE GROUPS
MATHEMATICAL MODELS
MATRICES
MATRIX ELEMENTS
MATTER
MEASURING INSTRUMENTS
MESONS
NUCLEON-ANTINUCLEON INTERACTIONS
OBE MODEL
PAIR PRODUCTION
PARTIAL DIFFERENTIAL EQUATIONS
PARTICLE INTERACTIONS
PARTICLE MODELS
PARTICLE PRODUCTION
PARTICLE PROPERTIES
PERIPHERAL MODELS
POLARIZATION
PROTON-ANTIPROTON INTERACTIONS
RADIATION DETECTORS
S MATRIX
SCHROEDINGER EQUATION
SPIN
STRANGE MESONS
STRANGE PARTICLES
STRANGENESS
SU GROUPS
SU-3 GROUPS
SYMMETRY GROUPS
VECTOR MESONS
WAVE EQUATIONS