Evidence for the associated production of a W boson and a top quark in ATLAS at sqrt{s}=7 TeV

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68378271%3A_____%2F12%3A00388969" target="_blank" >RIV/68378271:_____/12:00388969 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1016/j.physletb.2012.08.011" target="_blank" >http://dx.doi.org/10.1016/j.physletb.2012.08.011</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.physletb.2012.08.011" target="_blank" >10.1016/j.physletb.2012.08.011</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Evidence for the associated production of a W boson and a top quark in ATLAS at sqrt{s}=7 TeV

Popis výsledku v původním jazyce

This letter presents evidence for the associated production of a W boson and a top quark using 2.05 fb^-1 of pp collision data at sqrt(s) = 7 TeV accumulated with the ATLAS detector at the LHC. An approach based on boosted decision trees has been developed to improve the discrimination of single top-quark Wt events from background. A template fit to the final classifier distributions is performed to determine the cross-section. The result is incompatible with the background-only hypothesis at the 3.3 sigma level, the expected sensitivity assuming the Standard Model production rate being 3.4 sigma. The corresponding cross-section is determined and found to be sigma_Wt = 16.8 +/- 2.9 (stat) +/- 4.9 (syst) pb, in good agreement with the Standard Model expectation. From this result the CKM matrix element |V_{tb}| = 1.03{+0.16}{-0.19} is derived assuming that the Wt production through |V_{ts}| and |V_{td}| is small.

Název v anglickém jazyce

Evidence for the associated production of a W boson and a top quark in ATLAS at sqrt{s}=7 TeV

Popis výsledku anglicky

This letter presents evidence for the associated production of a W boson and a top quark using 2.05 fb^-1 of pp collision data at sqrt(s) = 7 TeV accumulated with the ATLAS detector at the LHC. An approach based on boosted decision trees has been developed to improve the discrimination of single top-quark Wt events from background. A template fit to the final classifier distributions is performed to determine the cross-section. The result is incompatible with the background-only hypothesis at the 3.3 sigma level, the expected sensitivity assuming the Standard Model production rate being 3.4 sigma. The corresponding cross-section is determined and found to be sigma_Wt = 16.8 +/- 2.9 (stat) +/- 4.9 (syst) pb, in good agreement with the Standard Model expectation. From this result the CKM matrix element |V_{tb}| = 1.03{+0.16}{-0.19} is derived assuming that the Wt production through |V_{ts}| and |V_{td}| is small.

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

BF - Elementární částice a fyzika vysokých energií

OECD FORD obor

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Projekt

<a href="/cs/project/LA08032" target="_blank" >LA08032: Mezinárodní experiment ATLAS-CERN</a><br>

Návaznosti

Z - Vyzkumny zamer (s odkazem do CEZ)

Rok uplatnění

2012

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Physics Letters. B

ISSN

0370-2693

e-ISSN

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Svazek periodika

716

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

18

Strana od-do

142-159

Kód UT WoS článku

000309621400007

EID výsledku v databázi Scopus

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