Second-order QCD corrections to heavy-quark forward-backward asymmetries

Electroweak production of top-quark pairs ine+e−annihilation at NNLO in QCD: The vector current contributions

“…Total cross sections are known to NNLO in the threshold expansions [8][9][10][11][12] and high-energy expansions [13][14][15][16][17]. Results for the forwardbackward asymmetry are also known in the small mass approximation [18][19][20]. In the near future, the threshold cross section at NNNLO will also be available [21][22][23].…”

Two-loop QCD corrections to the heavy quark form factors: the vector contributions

“…The present theoretical description of A b f b includes the fully massive next-toleading order (NLO) electroweak [2] and fully massive NLO QCD [3,4] corrections as well as the leading terms from the next-to-next-to-leading order (NNLO) QCD corrections [5] (see also [6,7]), which were obtained based on the massless approximation plus leading logarithmic mass terms. Given the substantial discrepancy between the experimental result and the theoretical expectation and the high impact on the Higgs mass determination, a more precise theoretical understanding of A b f b is clearly desired.…”

Master integrals for the 2-loop QCD virtual corrections to the forward–backward asymmetry

“…The precision reached by the actual and aimed at future measurements requires, from the theoretical counterpart, the control of the second-order perturbative corrections. As concerning QCD, the order O(α 2 S ) corrections for massless quarks were calculated numerically in [4] and analytically in [5]. For the b quarks the order O(α 2 S ) corrections were calculated numerically in [6], retaining terms that do not vanish in the small-mass limit (constants and logarithmically-enhanced terms), but neglecting both terms containing linear mass corrections, like m b /Q, and terms in which such a ratio is enhanced by a power of the logarithm log(Q/m b ).…”