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DIRAC Experiment at CERN: Lifetime Measurement of Pionium

Juerg Schacher
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Abstract

The DIRAC experiment, a magnetic double arm spectrometer, aims to measure the $π^+π^-$ atom lifetime with 10% precision, using the high intensity 24 GeV/c proton beam of the CERN Proton Synchrotron. Since the value of this lifetime of order $10^{-15}$~s is dictated by strong interaction at low energy, a precise measurement of this quantity enables to study characteristic pion parameters in detail and to submit predictions of QCD to a severe check.

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Juerg Schacher. 1998-08-25. DIRAC Experiment at CERN: Lifetime Measurement of Pionium. https://arxiv.org/abs/hep-ph/9808407

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