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Title: Regge-plus-resonance treatment of the p({gamma},K{sup +}){sigma}{sup 0} and p({gamma},K{sup 0}){sigma}{sup +} reactions at forward kaon angles

Abstract

An effective-Lagrangian framework for K{sigma} photoproduction from the proton is presented. The proposed model is applicable at forward kaon angles and photon lab energies from threshold up to 16 GeV. The high-energy part of the p({gamma},K{sup +}){sigma}{sup 0} and p({gamma},K{sup 0}){sigma}{sup +} amplitudes is expressed in terms of Regge-trajectory exchange in the t channel. By supplementing this Regge background with a number of s-channel resonances, the model is extended toward the resonance region. The resulting ''Regge-plus-resonance'' (RPR) approach has the advantage that the background contributions involve only a few parameters, which can be largely constrained by the high-energy data. This work compares various implementations of the RPR model, and explores which resonance contributions are required to fit the data presently at hand. It is demonstrated that, through the inclusion of one K and two K* trajectories, the RPR framework provides an efficient and unified description of the K{sup +}{sigma}{sup 0} and K{sup 0}{sigma}{sup +} photoproduction channels over an extensive energy range.

Authors:
; ; ;  [1];  [2]
  1. Department of Subatomic and Radiation Physics, Ghent University, Proeftuinstraat 86, B-9000 Gent (Belgium)
  2. (United Kingdom)
Publication Date:
OSTI Identifier:
20995229
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. C, Nuclear Physics; Journal Volume: 75; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevC.75.045204; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; COMPARATIVE EVALUATIONS; GEV RANGE 10-100; KAONS NEUTRAL; LAGRANGIAN FUNCTION; PHOTONS; PHOTOPRODUCTION; POTASSIUM IONS; PROTONS; REGGE TRAJECTORIES; RESONANCE; S CHANNEL; SIGMA NEUTRAL PARTICLES; SIGMA PLUS PARTICLES; T CHANNEL

Citation Formats

Corthals, T., Cauteren, T. Van, Ryckebusch, J., Ireland, D. G., and University of Glasgow, Glasgow G12 8QQ. Regge-plus-resonance treatment of the p({gamma},K{sup +}){sigma}{sup 0} and p({gamma},K{sup 0}){sigma}{sup +} reactions at forward kaon angles. United States: N. p., 2007. Web. doi:10.1103/PHYSREVC.75.045204.
Corthals, T., Cauteren, T. Van, Ryckebusch, J., Ireland, D. G., & University of Glasgow, Glasgow G12 8QQ. Regge-plus-resonance treatment of the p({gamma},K{sup +}){sigma}{sup 0} and p({gamma},K{sup 0}){sigma}{sup +} reactions at forward kaon angles. United States. doi:10.1103/PHYSREVC.75.045204.
Corthals, T., Cauteren, T. Van, Ryckebusch, J., Ireland, D. G., and University of Glasgow, Glasgow G12 8QQ. Sun . "Regge-plus-resonance treatment of the p({gamma},K{sup +}){sigma}{sup 0} and p({gamma},K{sup 0}){sigma}{sup +} reactions at forward kaon angles". United States. doi:10.1103/PHYSREVC.75.045204.
@article{osti_20995229,
title = {Regge-plus-resonance treatment of the p({gamma},K{sup +}){sigma}{sup 0} and p({gamma},K{sup 0}){sigma}{sup +} reactions at forward kaon angles},
author = {Corthals, T. and Cauteren, T. Van and Ryckebusch, J. and Ireland, D. G. and University of Glasgow, Glasgow G12 8QQ},
abstractNote = {An effective-Lagrangian framework for K{sigma} photoproduction from the proton is presented. The proposed model is applicable at forward kaon angles and photon lab energies from threshold up to 16 GeV. The high-energy part of the p({gamma},K{sup +}){sigma}{sup 0} and p({gamma},K{sup 0}){sigma}{sup +} amplitudes is expressed in terms of Regge-trajectory exchange in the t channel. By supplementing this Regge background with a number of s-channel resonances, the model is extended toward the resonance region. The resulting ''Regge-plus-resonance'' (RPR) approach has the advantage that the background contributions involve only a few parameters, which can be largely constrained by the high-energy data. This work compares various implementations of the RPR model, and explores which resonance contributions are required to fit the data presently at hand. It is demonstrated that, through the inclusion of one K and two K* trajectories, the RPR framework provides an efficient and unified description of the K{sup +}{sigma}{sup 0} and K{sup 0}{sigma}{sup +} photoproduction channels over an extensive energy range.},
doi = {10.1103/PHYSREVC.75.045204},
journal = {Physical Review. C, Nuclear Physics},
number = 4,
volume = 75,
place = {United States},
year = {Sun Apr 15 00:00:00 EDT 2007},
month = {Sun Apr 15 00:00:00 EDT 2007}
}
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