Abstract
The first observation of the production of a boson with a single charm quark () jet in collisions at is reported. The analysis uses data corresponding to , recorded with the CDF II detector at the Fermilab Tevatron. Charm quark candidates are selected through the identification of an electron or muon from charm-hadron semileptonic decay within a hadronic jet, and a signal is observed with a significance of 5.7 standard deviations. The production cross section is measured to be and is in agreement with theoretical expectations. From this result the magnitude of the quark-mixing matrix element is derived, along with a lower limit of at the 95% confidence level, assuming that the production through to quark coupling is dominant.
- Received 10 September 2012
DOI:https://doi.org/10.1103/PhysRevLett.110.071801
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