Eur. Phys. J. A 11, 185-208 (2001)
Dispersion relation formalism for virtual Compton scattering off the proton
B. Pasquini1, M. Gorchtein2, D. Drechsel2, A. Metz3 and M. Vanderhaeghen21 ECT*, I-38050 Villazzano, Trento, and INFN, Trento, Italy
2 Institut für Kernphysik, Johannes-Gutenberg-Universität, D-55099 Mainz, Germany
3 Division of Physics and Astronomy, Faculty of Science, Vrije Universiteit, 1081 HV Amsterdam, The Netherlands
marcvdh@kph.uni-mainz.de
(Received: 14 March 2001 Communicated by V. Vento)
Abstract
We present in detail a dispersion relation formalism for virtual
Compton scattering (VCS) off the proton from threshold into the
-resonance region.
Such a formalism can be used
as a tool to extract the generalized polarizabilities of the proton from
both unpolarized and polarized VCS observables over a larger energy
range. We present calculations for existing and forthcoming VCS
experiments and demonstrate that the VCS observables in the energy region
between pion production threshold and the
-resonance
show an enhanced sensitivity to the generalized polarizabilities.
11.55.Fv - Dispersion relations.
13.40.-f - Electromagnetic processes and properties.
13.60.Fz - Elastic and Compton scattering.
14.20.Dh - Protons and neutrons.
© Società Italiana di Fisica, Springer-Verlag 2001