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arXiv · 1304.3618

Low-energy photon and pion scattering in holographic QCD

Pietro Colangelo·Juan Jose Sanz-Cillero·Fen Zuo
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Abstract

Using holographic models where chiral symmetry is broken through IR b.c.'s, we determine a novel set of relations between QCD matrix elements. In particular, we find that the amplitudes of the three processes pi pi->pi pi, gamma gamma->pi pi and gamma->pi pi pi involve a single scalar function h(Q^2) given by a suitable 5D integral of the EoM Green's function. In a phenomenological analysis of gamma gamma->pi pi we find an overall agreement with the experimental cross section for a broad range of energy. Moreover, the polarizabilities at low energies show a fair agreement between the holographic approach, previous computations and experiment.

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Pietro Colangelo, Juan Jose Sanz-Cillero, Fen Zuo. 2013-04-12. Low-energy photon and pion scattering in holographic QCD. https://doi.org/10.1007/jhep06(2013)020

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