Measurement of the single-top-quark t-channel cross section in pp collisions at sqrt(s) = 7 TeV

TL;DR

This paper reports a measurement of the single-top-quark t-channel production cross section at 7 TeV using CMS data, employing two analysis methods, and finds results consistent with the Standard Model predictions.

Contribution

It introduces two complementary analysis approaches for measuring the t-channel single-top-quark production cross section at the LHC.

Findings

Measured cross section: 67.2 +/- 6.1 pb

CKM matrix element |V[tb]|: 1.020 +/- 0.046 (meas.) +/- 0.017 (theor.)

Results agree with Standard Model predictions

Abstract

A measurement of the single-top-quark t-channel production cross section in pp collisions at sqrt(s) = 7 TeV with the CMS detector at the LHC is presented. Two different and complementary approaches have been followed. The first approach exploits the distributions of the pseudorapidity of the recoil jet and reconstructed top-quark mass using background estimates determined from control samples in data. The second approach is based on multivariate analysis techniques that probe the compatibility of the candidate events with the signal. Data have been collected for the muon and electron final states, corresponding to integrated luminosities of 1.17 and 1.56 inverse femtobarns, respectively. The single-top-quark production cross section in the t-channel is measured to be 67.2 +/- 6.1 pb, in agreement with the approximate next-to-next-to-leading-order standard model prediction. Using the standard model electroweak couplings, the CKM matrix element abs(V[tb]]) is measured to be 1.020 +/- 0.046 (meas.) +/- 0.017 (theor.).