Chiral Low-Energy Constants
نویسنده
چکیده
The progress in determining the coupling constants of mesonic chiral Lagrangians is reviewed, with emphasis on the work performed in three successive European Networks (Eurodaphne I and II, Euridice). Reliable estimates of those constants are essential for making full use of next-to-next-to-leading-order calculations in chiral perturbation theory. The precision in the values of the strong coupling constants of O(p4) has been increasing steadily over the years. The situation is less satisfactory in the nonleptonic weak sector where further phenomenological input and more theoretical work are needed. A lot of progress has recently been achieved for electromagnetic coupling constants occurring in radiative corrections for mesonic processes at low energies. Presented at The Final Euridice Meeting, Kazimierz, Poland, Aug. 2006 Supported in part by EU contract No. MRTN-CT-2006-035482 (FLAVIAnet)
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