The first observation of the production of a W boson with a single charm quark (c) jet in pp̄ collisions at √s=1.96 TeV is reported. The analysis uses data corresponding to 4.3 fb-1, 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 Wc signal is observed with a significance of 5.7 standard deviations. The production cross section σ Wc(pTc>20 GeV/c,|ηc|<1.5) ×B(W→ℓν) is measured to be 13.6-3.1+3.4 pb and is in agreement with theoretical expectations. From this result the magnitude of the quark-mixing matrix element Vcs is derived, |Vcs|=1. 08±0.16 along with a lower limit of |Vcs|>0.71 at the 95% confidence level, assuming that the Wc production through c to s quark coupling is dominant. © 2013 American Physical Society.
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1103/PhysRevLett.110.071801|
|Codice identificativo ISI:||WOS:000314870300003|
|Codice identificativo Scopus:||2-s2.0-84874057616|
|Titolo:||Observation of the production of a W boson in association with a single charm quark|
|Appare nelle tipologie:||1.1 Articolo in rivista|