Eta and Eta’ Physics
نویسنده
چکیده
This talk describes the reasons why η and η decays are an interesting topic of study for both theory and experiment. The main part discusses the results of the recent calculation of η → 3π at two-loop order in ChPT. Some puzzling aspects of the results compared to earlier dispersive calculations are highlighted. I also like to remind the reader of the use of η and η decays for studying the anomaly. Plenary talk given at MENU07, September 10-14, 2007 Jülich, Germany ETA AND ETA’ PHYSICS IKP, Forschungzentrum Jülich, Germany Johan Bijnens Department of Theoretical Physics Lund University Sölvegatan 14A SE 22362 Lund, Sweden Abstract This talk describes the reasons why η and η decays are an interesting topic of study for both theory and experiment. The main part discusses the results of the recent calculation of η → 3π at two-loop order in ChPT. Some puzzling aspects of the results compared to earlier dispersive calculations are highlighted. I also like to remind the reader of the use of η and η decays for studying the anomaly.This talk describes the reasons why η and η decays are an interesting topic of study for both theory and experiment. The main part discusses the results of the recent calculation of η → 3π at two-loop order in ChPT. Some puzzling aspects of the results compared to earlier dispersive calculations are highlighted. I also like to remind the reader of the use of η and η decays for studying the anomaly.
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