Search for FCNC single top-quark production at with the ATLAS detector
- 作者：ATLAS Collaboration鈰?/sup>
- 关键词：Top physics ; Heavy-quark production ; FCNC ; Single top quark
- 刊名：Physics Letters B
- 出版年：2012
- 期刊代码：58_03702693
- 类别：ph
- 出版时间：12 June, 2012
- 卷：712
- 期：4-5
- 页码：351-369
- 文件大小：1281 K
摘要
A search for the production of single top-quarks via flavour-changing neutral-currents is presented. Data collected with the ATLAS detector at a centre-of-mass energy of , corresponding to an integrated luminosity of 2.05 fb鈭?, are used. Candidate events with a semileptonic top-quark decay signature are classified as signal- or background-like events by using several kinematic variables as input to a neural network. No signal is observed in the neural network output distribution and a Bayesian upper limit is placed on the production cross-section. The observed upper limit at 95%confidence level on the cross-section multiplied by the branching fraction is measured to be . This upper limit is converted using a model-independent approach into upper limits on the coupling strengths and , where 螞 is the new physics scale, and on the branching fractions and .