A ug 2 00 9 Quadrupole polarizabilities of the pion in the Nambu – Jona - Lasinio model ⋆
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چکیده
The electromagnetic dipole and quadrupole polarizabilities of the neutral and charged pions are calculated in the Nambu–Jona-Lasinio model. Our results agree with the recent experimental analysis of these quantities based on Dispersion Sum Rules. Comparison is made with the results from the Chiral Perturbation Theory.
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تاریخ انتشار 2009