PRODUCTION OF STRANGE PARTICLES BY $pi$- NUCLEON AND PHOTONUCLEON INTERACTIONS NEAR THRESHOLD

Journal Article · Tue Jul 15 04:00:00 EDT 1958 · Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D

DOI:https://doi.org/10.1103/PhysRev.111.632· OSTI ID:4305794

Adair, R K

An investigation of the behavior of the pi -nucleon reaction cross sections near the strange particle threshold shows that the variation with energy of the LAMBDA /sup 0/-K cross section near the EPSILON -K threshold depends strongly upon the relative parities of the EPSILON and the flu hyperons. If the elements of the Wigner R matrix are nearly stationary near the EPSILON -K threshold, and if the the compound system is nearly independent of its mode of formation. the variation of the LAMBDA /sup 0/ and EPSILON cross sections is almost uniquely established from cross sections measured at one energy. In particular, the LAMBDA /sup 0/ cross section exhibits strong cusps at the EPSILON -K thresholds. Angular distributions and polarizations are discussed from the viewpoint of these assumptions. The photonucleon production of strange particles is shown to be closely related to the pi -nucleon production, essentially because the same final-state interaccions are important. The strength and characteristics of these interactions lead to the conclusion that the matrix elements for photonucleon production of strange particles will, in general, be strongly affected in magnitude by the final-state interactions and they will not be real, even at threshold. The analysis of cusps, which are predicted in the gamma + p yields pi + nucleon cross section at the LAMBDA /sup0/ + K threshold and the EPSILON + K threshold, and in the gamma + p yields LAMBDA /sup 0/ K reaction at the EPSILON + K threshold, should provide a means of determining the relative parities of the strange particles, in a manner almost independent of the dynamics of the reaction. (auth)

• Research Organization: Brookhaven National Lab., Upton, N.Y.
• NSA Number: NSA-12-016597
• OSTI ID: 4305794
• Journal Information: Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D, Journal Name: Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D Vol. Vol: 111; ISSN PHRVA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ANGULAR DISTRIBUTION
CROSS SECTIONS
DECAY
ENERGY
GROUP THEORY
INTERACTIONS
KAONS
LAMBDA PARTICLES
MATRICES
NUCLEONS
PARITY
PHOTONS
PHYSICS
PIONS
POLARIZATION
PRODUCTION
PROTONS
QUANTUM MECHANICS
SIGMA PARTICLES
STRANGE PARTICLES
VARIATIONS
WIGNER THEORY