Gauge invariance of meson photo- and electroproduction currents revisited

Abstract

An exact expression is derived for the meson production current off the nucleon for real and virtual photons which cleanly separates, in a model-independent manner, a tree-level expression that manifestly preserves local gauge invariance in terms of a generalized Ward-Takahashi identity from transverse final-state-interaction (FSI) terms. As discussed in some detail, this exact formulation is particularly well suited for implementing approximation schemes of exchange-current and FSI contributions (which in practice generally will be necessary) at any level of sophistication without violating local gauge invariance.

6 pages, 4 figures

References in corpus (6)

• Nucleon and Delta resonances in K Sigma(1385) photoproduction from nucleons
• Gauge-invariant approach to meson photoproduction including the final-state interaction
• Photoproduction of Xi off nucleons
• Nucleon resonances in $\gamma p\to \omega p$ reaction
• Effects of $N(2000){5/2}^{+}$ on $\gamma p\to K^{+}\Lambda (1405)$
• Measurement and analysis of the pp -> pp gamma reaction at 310 MeV

Cited by in corpus (1)

• Coupled-channel analysis of pion- and eta-electroproduction with the Jülich-Bonn-Washington model