Determination of the top-quark pole mass and strong coupling constant from the tt production cross section in pp collisions at root s=7 TeV

Abstract

The inclusive cross section for top-quark pair production measured by the CMS experiment in proton–proton collisions at a center-of-mass energy of 7 TeV is compared to the QCD prediction at next-to-next-to-leading order with various parton distribution functions to determine the top-quark pole mass, View the MathML source, or the strong coupling constant, αS. With the parton distribution function set NNPDF2.3, a pole mass of View the MathML source is obtained when constraining αS at the scale of the Z boson mass, mZ, to the current world average. Alternatively, by constraining View the MathML source to the latest average from direct mass measurements, a value of View the MathML source is extracted. This is the first determination of αS using events from top-quark production.