Precision Spectroscopy of Pionic Atoms: from Pion Mass Evaluation to Tests of Chiral Perturbation Theory
نویسنده
چکیده
Preliminary results of the strong interaction shift and width in pionic hydrogen (πH) using an X-ray spectrometer with spherically bent crystals and CCDs as X-ray detector are presented. In the experiment at the Paul Scherrer Institute three different (np → 1s) transitions in πH were measured. Moreover the pion mass measurement using the (5 → 4) transitions in pionic nitrogen and muonic oxygen is presented
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