Gauge Invariant Two-Photon-Exchange Contributions in $e^{-}{\pi }^{+}\to e^{-}{\pi }^{+}$

Abstract

The gauge invariant two-photon exchange (TPE) contributions in $e^{-}{\pi }^{+}\to e^{-}{\pi }^{+}$ are discussed at hadronic level. The contact term is added to keep the full amplitude gauge invariant by two methods: one is to multiply form factors with the point-like particles scattering amplitude and another is to construct a gauge invariant Lagangian. The practical calculations show the TPE corrections by these two methods are almost the same, while the later method is favored when extending the discussion to processes including two charged finite-size particles like $ep\to en{\pi }^{+}$.

5 pages, 2 fugures

References in corpus (11)

• Global analysis of proton elastic form factor data with two-photon exchange corrections
• Determination of the Charged Pion Form Factor at Q2=1.60 and 2.45 (GeV/c)2
• Charged pion form factor between Q^2=0.60 and 2.45 GeV^2. II. Determination of, and results for, the pion form factor
• Charged pion form factor between $Q^2$=0.60 and 2.45 GeV${}^2$. I. Measurements of the cross section for the ${}^1$H($e,e^{\prime }{\pi }^{+}$)$n$ reaction
• Two-photon exchange in dispersion approach
• Two-photon exchange in elastic electron-proton scattering : QCD factorization approach
• Is there model-independent evidence of the two-photon-exchange effect in the electron-proton elastic scattering cross section?
• Perturbative QCD predictions for two-photon exchange
• Two-photon exchange at low Q^2
• Reexamination of phenomenological two-photon exchange corrections to the proton form factors and e+-p scattering
• Two Photon Exchange Contributions to Elastic e + p --> e + p Process in a Nonlocal Field Formalism

Cited by in corpus (3)

• Two photon exchange in elastic electron scattering off hadronic systems
• Two-Photon-Exchange effects in $ep\to en{\pi }^{+}$ and their corrections to separated cross sections ${\sigma }_{\text{L,T,LT,TT}}$ at small $-t$
• Two-photon exchange effects in $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}$ at small $\sqrt{s}$