Observation of the Charge Symmetry Breaking d + d -> 4He + pi0 Reaction Near Threshold

E. J. Stephenson; A. D. Bacher; C. E. Allgower; A. Gardestig; C. Lavelle; G. A. Miller; H. Nann; J. Olmsted; P. V. Pancella; M. A. Pickar; J. Rapaport; T. Rinckel; A. Smith; H. M. Spinka; U. van Kolck

doi:10.1103/physrevlett.91.142302

arXiv · nucl-ex/0305032

Observation of the Charge Symmetry Breaking d + d -> 4He + pi0 Reaction Near Threshold

E. J. Stephenson·A. D. Bacher·C. E. Allgower·A. Gardestig·C. Lavelle·G. A. Miller·H. Nann·J. Olmsted·P. V. Pancella·M. A. Pickar·J. Rapaport·T. Rinckel·A. Smith·H. M. Spinka·U. van Kolck

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Abstract

We report the first observation of the charge symmetry breaking d + d -> 4He + pi0 reaction near threshold at the Indiana University Cyclotron Facility. Kinematic reconstruction permitted the separation of 4He + pi0 events from double radiative capture 4He + gamma + gamma events. We measured total cross sections for neutron pion production of 12.7 +- 2.2 pb at 228.5 MeV and 15.1 +- 3.1 pb at 231.8 MeV. The uncertainty is dominated by statistical errors.

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E. J. Stephenson, A. D. Bacher, C. E. Allgower, A. Gardestig, C. Lavelle, G. A. Miller, H. Nann, J. Olmsted, P. V. Pancella, M. A. Pickar, J. Rapaport, T. Rinckel, A. Smith, H. M. Spinka, U. van Kolck. 2003-05-28. Observation of the Charge Symmetry Breaking d + d -> 4He + pi0 Reaction Near Threshold. https://doi.org/10.1103/physrevlett.91.142302

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