Pion-nucleon and pion-nucleus interactions at intermediate energies

Thesis/Dissertation · Wed Dec 31 23:00:00 EST 1986

OSTI ID:5466529

Parnell, G E

Models of the pion-nucleon interaction must be relativistic and field theoretic. This work models those partial waves (S-, D-, and F-waves) of the interaction exhibiting resonant behavior with a new doorway resonance model, which is both relativistic and field theoretic. This model is demonstrated to be a generalization of previous Chew-Low models with the improvement of allowing nucleon recoil and is applied to the P{sub 13}, P{sub 31}, and P{sub 33} channels. Other partial waves are modeled by the relativistic generalization, developed in this work, of previous separable potential models. The results of the models are shown to compare favorably with the data. All models are free of kinematic singularities. These models are utilized to form a microscopic, momentum-space, isospin invariant optical potential to investigate the pion-nucleus isoelastic interaction in the energy region from 300 MeV to 500 MeV where data has only recently become available and where no prior theoretical work exists. The optical potential utilizes fully relativistic kinematics, and the fermi integration is performed exactly as well as by optimal factorization. The results are compared to recent data for O{degree} excitation functions for the isobar analogue state transitions in {sup 14}C and {sup 90}Zr. The observed rise in the cross section for energies above the resonance is reproduced by the theory, and, although not totally quantitative, the theoretical results indicate that the multiple scattering theory as defined and implemented here is significantly more convergent at the higher energies than at or below the resonance.

• Research Organization: Texas A and M Univ., College Station, TX (USA)
• OSTI ID: 5466529
• Country of Publication: United States
• Language: English

Related Subjects

645204 -- High Energy Physics-- Particle Interactions & Properties-Theoretical-- Strong Interactions & Properties
653003* -- Nuclear Theory-- Nuclear Reactions & Scattering
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CARBON 14
CARBON ISOTOPES
CHARGED-PARTICLE REACTIONS
CHEW-LOW METHOD
COMPARATIVE EVALUATIONS
DATA
ELASTIC SCATTERING
ENERGY RANGE
ENERGY-LEVEL TRANSITIONS
EVEN-EVEN NUCLEI
FIELD THEORIES
GENERAL RELATIVITY THEORY
HADRON REACTIONS
HADRON-HADRON INTERACTIONS
INFORMATION
INTERACTIONS
INTERMEDIATE MASS NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
LIGHT NUCLEI
MATHEMATICAL MODELS
MESON REACTIONS
MESON-BARYON INTERACTIONS
MESON-NUCLEON INTERACTIONS
MEV RANGE
MEV RANGE 100-1000
NUCLEAR REACTIONS
NUCLEI
NUMERICAL DATA
PARTIAL WAVES
PARTICLE INTERACTIONS
PION REACTIONS
PION-NUCLEON INTERACTIONS
POTENTIALS
RADIOISOTOPES
RELATIVITY THEORY
SCATTERING
SINGULARITY
STABLE ISOTOPES
THEORETICAL DATA
YEARS LIVING RADIOISOTOPES
ZIRCONIUM 90
ZIRCONIUM ISOTOPES