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Precision Spectroscopy of Pionic Atoms: From Pion Mass Evaluation to Tests of Chiral Perturbation Theory

Martino Trassinelli
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Abstract

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 $(np\to 1s)$ transitions in $πH$ were measured. Moreover the pion mass measurement using the $(5 \to 4)$ transitions in pionic nitrogen and muonic oxygen is presented

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Martino Trassinelli. 2004-09-14. Precision Spectroscopy of Pionic Atoms: From Pion Mass Evaluation to Tests of Chiral Perturbation Theory. https://arxiv.org/abs/physics/0409066

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