6533b85bfe1ef96bd12ba1af
RESEARCH PRODUCT
Radiative pion capture by a nucleon
Thomas R. HemmertRandy LewisC. UnkmeirHarold W. Fearingsubject
PhysicsNuclear and High Energy PhysicsParticle physicsHeavy baryon chiral perturbation theoryNuclear Theory010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyInverseFOS: Physical sciences01 natural sciencesJNuclear Theory (nucl-th)symbols.namesakeHigh Energy Physics - PhenomenologyPionHigh Energy Physics - Phenomenology (hep-ph)Dispersion relation0103 physical sciencesRadiative transfersymbolsddc:530010306 general physicsNucleonLagrangianFree parameterdescription
The differential cross sections for $\pi^- p \to \gamma n$ and $\pi^+ n \to \gamma p$ are computed up to $O(p^3)$ in heavy baryon chiral perturbation theory (HBChPT). The expressions at $O(p)$ and $O(p^2)$ have no free parameters. There are three unknown parameters at $O(p^3)$, low energy constants of the HBChPT Lagrangian, which are determined by fitting to experimental data. Two acceptable fits are obtained, which can be separated by comparing with earlier dispersion relation calculations of the inverse process. Expressions for the multipoles, with emphasis on the p-wave multipoles, are obtained and evaluated at threshold. Generally the results obtained from the best of the two fits are in good agreement with the dispersion relation predictions.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2000-01-01 |