Abstract
A search has been carried out for neutral charm production in 5,108 proton-emulsion interactions at 400 GeV/c. Nine charm candidates have been observed in our fiducial volume which extends from 100 μm-1,000 μm in the forward cone. One of these is a 4-prong and the others are 2-prong events with opening angle>10 mrad and momenta of both decay tracks>150 MeV/c. Search for associated charm decays was made in an extended fiducial volume around the primary stars of these nine candidates. This yielded two neutral 2-prong events, one associated with the 4-prong and the other with a 2-prong candidate. All unassociated candidates are consistent with being backgrounds due toK s , Λ decays, neutral interactions and γ conversions whereas the background to associated events is negligible. Based on the two associated decays the inclusive cross section forD 0, −0 production is determined as 27±20 μb/nucleon. Detailed measurements on the 4-prong candidate lead to the identification of one decay track as an electron and another as a kaon. This is interpreted as a semi-leptonic, Cabbibo favouredD 0/D −0 decay.
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Aziz, T., Ahmad, S., Ahrar, H. et al. Neutral charm production in 400 GeV proton-emulsion interactions. Z. Phys. C - Particles and Fields 26, 13–18 (1984). https://doi.org/10.1007/BF01572535
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DOI: https://doi.org/10.1007/BF01572535