INVESTIGADORES
MONTICELLI Fernando Gabriel
artículos
Título:
Measurement of the t-channel single top-quark production cross section in pp collisions at √s = 7 TeV with the ATLAS detector
Autor/es:
ATLAS COLLABORATION, G. AAD, F. MONTICELLI, ET AL
Revista:
PHYSICS LETTERS B
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Lugar: Amsterdam; Año: 2012 vol. 213 p. 1 - 23
ISSN:
0370-2693
Resumen:
We report a measurement of
the cross section of single top-quark production in the t-channel using
1.04 fb^-1 of pp collision data at sqrt(s) = 7 TeV recorded with the
ATLAS detector at the LHC. Selected events feature one electron or muon,
missing transverse momentum, and two or three jets, exactly one of them
identified as originating from a b quark. The cross section is measured
by fitting the distribution of a multivariate discriminant constructed
with a neural network, yielding sigma(t)= 83 +/- 4 (stat.) +20 -19
(syst) pb which is in good agreement with the prediction of the Standard
Model. Using the ratio of the measured to the theoretically predicted
cross section and assuming that the top-quark-related CKM matrix
elements obey the relation |V(tb)| >> |V(ts)|, |V(td)|, the
coupling strength at the W-t-b vertex is determined to be |V(tb)| = 1.13
+0.14 -0.13. If it is assumed that |V(tb)| <= 1 a lower limit of
|V(tb)|>0.75 is obtained at the 95% confidence level.