Two-pion-exchange potential and the {pi}{ital N} amplitude

Journal Article · Fri Nov 01 04:00:00 EST 1996 · Physical Review, C

DOI:https://doi.org/10.1103/PhysRevC.54.2235· OSTI ID:389407

Pena, M T ^[1]; Gross, F; Surya, Y ^[2]

---

1. Centro de Fisica Nuclear da Universidade de Lisboa, 1699 Lisboa Codex, Portugal and Instituto Superior Tecnico, 1096 Lisboa Codex (Portugal)
2. College of William and Mary, Williamsburg, Virginia 23185 and CEBAF, 12000 Jefferson Avenue, Newport News, Virginia 23606 (United States)

We discuss the two-pion-exchange (TPE) potential which emerges from a box diagram with one nucleon (the spectator) restricted to its mass shell, and the other nucleon line replaced by a subtracted, covariant {pi}{ital N} scattering amplitude which includes {Delta}, Roper, and {ital D}{sub 13} isobars, as well as contact terms and off-shell (nonpole) dressed nucleon terms. The {pi}{ital N} amplitude satisfies chiral symmetry constraints and fits {pi}{ital N} data below {approximately} 700 MeV pion energy. We find that this TPE potential can be well approximated by the exchange of an effective sigma and delta meson, with parameters close to the ones used in one-boson-exchange models that fit {ital NN} data below the pion production threshold. {copyright} {ital 1996 The American Physical Society.}

• DOE Contract Number: FG05-88ER40435
• OSTI ID: 389407
• Journal Information: Physical Review, C, Journal Name: Physical Review, C Journal Issue: 5 Vol. 54; ISSN PRVCAN; ISSN 0556-2813
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
BOSON-EXCHANGE MODELS
EXCHANGE INTERACTIONS
PION-NUCLEON INTERACTIONS
PIONS
POTENTIALS
SCATTERING AMPLITUDES
SIGMA PARTICLES