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Detailed comparison of the pp -> π^+pn and pp -> π^+d reactions at 951 MeV

GEM collaboration·M. Abdel-Bary
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Abstract

The positively charged pions produced in proton-proton collisions at a beam momentum of 1640 MeV/c were measured in the forward direction with a high resolution magnetic spectrograph. The missing mass distribution shows the bound state (deuteron) clearly separated from the $pn$ continuum. Despite the very good resolution, there is no evidence for any significant production of the $pn$ system in the spin-singlet state. However, the $σ(pp\to π^+pn)/σ(pp\to π^+d)$ cross section ratio is about twice as large as that predicted from $S$-wave final-state-interaction theory and it is suggested that this is due to $D$-state effects in the $pn$ system.

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GEM collaboration, M. Abdel-Bary. 2004-12-01. Detailed comparison of the pp -> π^+pn and pp -> π^+d reactions at 951 MeV. https://doi.org/10.1016/j.physletb.2005.01.100

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