Ústav technické a experimentální fyziky Institute of Experimental and Applied Physics

Measurement of the t-channel single top-quark production cross section in pp collisions at root s=7 TeV with the ATLAS detector

NázevTitle
Measurement of the t-channel single top-quark production cross section in pp collisions at root s=7 TeV with the ATLAS detectorMeasurement of the t-channel single top-quark production cross section in pp collisions at root s=7 TeV with the ATLAS detector
Druh výsledkuResult type
Článek v časopiseJournal article
AutořiAuthors
G. Aad, B. Abbott, J. Abdallah, S. Abdel Khalek, K. Augsten, T. Holý, T. Horažďovský, Z. Hubáček, J. Jakůbek, Z. Kohout, V. Král, F. Krejčí, S. Pospíšil, V. Šimák, T. Slavíček, K. Smolek, J. Sodomka, M. Solar, J. Šolc, B. Sopko, V. Sopko, I. Štekl, D. Tureček, V. Vacek, M. Vlasák, P. Vokáč
DOIDOI
10.1016/j.physletb.2012.09.031
Časopis / citaceJournal / citation
Physics Letters B. 2012, 717(4-5), 330-350. ISSN 0370-2693.
RokYear
2012
JazykLanguage
eng
WoSWoS
000310863300008
ScopusScopus
2-s2.0-85041779750
RIVRIV
RIV/68407700:21220/12:00202662!RIV13-MSM-21220___
ProjektProject
Matematické, počítačové a experimentální metody ve fyziceMathematical, Computer and Experimental Methods in Physics; Mezinárodní experiment ATLAS-CERNInternational Experiment ATLAS-CERN; Mezinárodní experiment ATLAS-CERNInternational Experiment ATLAS-CERN; Matematické, počítačové a experimentální metody ve fyziceMathematical, Computer and Experimental Methods in Physics; Fundamentální experimenty ve fyzice mikrosvětaFundamental Experiments in Physics of Microworld; Centrum částicové fyzikyCenter for Particle Physics

AbstraktAbstract

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 root 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.)(-19)(+20) (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 vertical bar V-tb vertical bar >> vertical bar V-ts vertical bar, vertical bar V-td vertical bar, the coupling strength at the W-t-b vertex is determined to be vertical bar V-tb vertical bar = 1.13(-0.13)(+0.14). If it is assumed that vertical bar V-tb vertical bar <= 1 a lower limit of vertical bar V-tb vertical bar > 0.75 is obtained at the 95% confidence level.

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 root 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.)(-19)(+20) (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 vertical bar V-tb vertical bar >> vertical bar V-ts vertical bar, vertical bar V-td vertical bar, the coupling strength at the W-t-b vertex is determined to be vertical bar V-tb vertical bar = 1.13(-0.13)(+0.14). If it is assumed that vertical bar V-tb vertical bar <= 1 a lower limit of vertical bar V-tb vertical bar > 0.75 is obtained at the 95% confidence level.