Roy-Steiner equations for pion-nucleon scattering
| Autor: | Christoph Ditsche, Ulf-G. Meißner, Bastian Kubis, Martin Hoferichter |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2012 |
| Předmět: |
Nuclear and High Energy Physics
Work (thermodynamics) Particle physics scattering amplitude [pi nucleon] Nuclear Theory dispersion relation partial wave FOS: Physical sciences Nuclear Theory (nucl-th) Pion High Energy Physics - Phenomenology (hep-ph) unitarity ddc:530 crossing [symmetry] numerical calculations Mathematical physics Physics Unitarity Scattering Closed system Crossing Order (ring theory) form factor: electromagnetic [nucleon] analytic properties High Energy Physics - Phenomenology Nucleon spectral representation |
| Zdroj: | Journal of high energy physics 1206(6),-043 (2012). doi:10.1007/JHEP06(2012)043 |
| DOI: | 10.1007/JHEP06(2012)043 |
| Popis: | Starting from hyperbolic dispersion relations, we derive a closed system of Roy-Steiner equations for pion-nucleon scattering that respects analyticity, unitarity, and crossing symmetry. We work out analytically all kernel functions and unitarity relations required for the lowest partial waves. In order to suppress the dependence on the high-energy regime we also consider once- and twice-subtracted versions of the equations, where we identify the subtraction constants with subthreshold parameters. Assuming Mandelstam analyticity we determine the maximal range of validity of these equations. As a first step towards the solution of the full system we cast the equations for the $\pi\pi\to\bar NN$ partial waves into the form of a Muskhelishvili-Omn\`es problem with finite matching point, which we solve numerically in the single-channel approximation. We investigate in detail the role of individual contributions to our solutions and discuss some consequences for the spectral functions of the nucleon electromagnetic form factors. Comment: 106 pages, 18 figures; version published in JHEP |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|