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Pion Generalized Dipole Polarizabilities by Virtual Compton Scattering $πe \to πeγ$

C. Unkmeir·A. Ocherashvili·T. Fuchs·M. A. Moinester·S. Scherer
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Abstract

We present a calculation of the cross section and the event generator of the reaction $πe\to πe γ$. This reaction is sensitive to the pion generalized dipole polarizabilities, namely, the longitudinal electric $α_L(q^2)$, the transverse electric $α_T(q^2)$, and the magnetic $β(q^2)$ which, in the real-photon limit, reduce to the ordinary electric and magnetic polarizabilities $\barα$ and $\barβ$, respectively. The calculation of the cross section is done in the framework of chiral perturbation theory at ${\cal O}(p^4)$. A pion VCS event generator has been written which is ready for implementation in GEANT simulation codes or for independent use.

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C. Unkmeir, A. Ocherashvili, T. Fuchs, M. A. Moinester, S. Scherer. 2001-07-03. Pion Generalized Dipole Polarizabilities by Virtual Compton Scattering $πe \to πeγ$. https://doi.org/10.1103/physrevc.65.015206

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