Unitary, relativistic resonance model for pi-N scattering

Journal Article · Mon Jun 01 04:00:00 EDT 1992 · Physical Review C

OSTI ID:954332

Gross, Franz; Surya, Yohanes

Pion nucleon scattering up to 600 MeV lab kinetic energy is described by a manifestly covariant wave equation in which the pion is restricted to its mass-shell.The kernel of the equation includes nucleon (N), Roper (N*), delta, and D(sub)13 poles, with their corresponding crossed pole terms approximated by contact interactions, and contact sigma and rho-like exchange terms.The pi-NN vertex is treated as a mixture of gamma^5 and gamma^mu gamma^5 coupling, with a mixingparameter lambda chosen so that the dressed nucleon pole will be unshifted by the interaction.Chiral symmetry is maintained at threshold.The resonance contributions are fully unitarized by the equation, with their widths determined by the dynamics included in the model.The delta and D(sub)13 are treated as a pure spin 3/2 particles, with no spin 1/2 amplitude in the S-channel.The complete development of this model, which gives a very good fit to all the data up to 600 MeV, is presented.

• Research Organization: Thomas Jefferson Lab National Accelerator Facility
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-84ER40150
• OSTI ID: 954332
• Report Number(s): CEBAF-TH-92-19
• Journal Information: Physical Review C, Journal Name: Physical Review C Vol. 47; ISSN 0556-2813; ISSN PRVCAN
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
AMPLITUDES
KERNELS
KINETIC ENERGY
MIXTURES
NUCLEONS
PIONS
RESONANCE
SCATTERING
SPIN
SYMMETRY
WAVE EQUATIONS