Observation of the Production of a W Boson in Association with a Single Charm Quark

• Main Authors: Gomez-Ceballos, Guillelmo (Contributor), Goncharov, Maxim (Contributor), Paus, Christoph M. E. (Contributor)
• Other Authors: Massachusetts Institute of Technology. Laboratory for Nuclear Science (Contributor)
• Format: Article
• Language: English
• Published: American Physical Society, 2013-04-10T20:09:26Z.
• Subjects: Article
• Online Access: Get fulltext

 The first observation of the production of a W boson with a single charm quark (c) jet in pp̅ collisions at √s=1.96  TeV is reported. The analysis uses data corresponding to 4.3  fb[superscript -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[subscript Wc](p[subscript Tc]>20  GeV/c,|η[subscript c]|<1.5)×B(W→ℓν) is measured to be 13.6[subscript -3.1][superscript +3.4]  pb and is in agreement with theoretical expectations. From this result the magnitude of the quark-mixing matrix element V[subscript cs] is derived, |V[subscript cs]|=1.08±0.16 along with a lower limit of |V[subscript cs]|>0.71 at the 95% confidence level, assuming that the Wc production through c to s quark coupling is dominant.