Related papers: QCD Matching Conditions at Thresholds
We discuss the resummation of the potentially large O((\beta_0\alpha_s)^n) QCD corrections to the total cross section of the process e^+e^- \to t \bar t near the threshold. In this approximation, the cross section factorization into the…
We present a consistent renormalization of the top and bottom quark/squark sector of the MSSM with complex parameters (cMSSM). Various renormalization schemes are defined, analyzed analytically and tested numerically in the decays Stop_2 ->…
A key problem in making precise perturbative QCD predictions is to set the proper renormalization scale of the running coupling. The extended renormalization group equations, which express the invariance of physical observables under both…
The magnitude of the strong interaction is characterized by $\alpha_s$, the coupling parameter in Quantum Chromodynamics (QCD), a parameter with an unexplained value in the Standard Model. In this paper, a candidate explanation for…
The top quark plays an important role in searches for physics beyond the SM, both as a dominant background and as a key signature for the signal. The most notable feature found in the top physics analyses in both ATLAS and CMS…
We discuss different choices that can be made when matching a general high-energy theory -- with the restriction that it should not contain heavy gauge bosons -- onto a general renormalisable effective field theory at one loop, with…
We try to review the main current ideas and points of view on the running coupling constant in QCD. We begin by recalling briefly the classic analysis based on the Renormalization Group with some emphasis on the exact solutions of the RG…
The interquark potential is constructed by making use of the new analytic running coupling in QCD. This running coupling arises under ``analytization'' of the renormalization group equation. The rising behavior of the interquark potential…
Precision determinations of the top-quark mass require theory predictions with a well-defined mass parameter in a given renormalization scheme. The top-quark's running mass in the MSbar scheme can be extracted with good precision from the…
We use the BLM procedure to eliminate the renormalization scale ambiguity in the evolution equation for the non-singlet deep-inelastic structure function $F_2^{\text NS}(x,Q).$ The scale of the QCD coupling in the $\overline{\text{MS}}$…
We show the results in [1,2] for computing the QCD contributions to the scale evolution of average gluon and quark jet multiplicities. The new results came due a recent progress in timelike small-x resummation obtained in the MSbar…
The quark-antiquark potential is constructed by making use of a new analytic running coupling in QCD. This running coupling arises under ``analytization'' of the renormalization group equation. The rising behavior of the quark-antiquark…
In QCD, the similarity of multiplicity distributions is violated i) by the running of the strong coupling constant alpha_s and ii) by the self-similar nature of parton cascades. It will be shown that the data collapsing behavior of P_n onto…
Stimulated by recent development of the calculation methods of the running quark masses $m_q(\mu)$ and renewal of the input data, for the purpose of making a standard table of $m_q(\mu)$ for convenience of particle physicists, the values of…
We present an evaluation of the running coupling constant and the quark mass renormalization factor for $N_f=2+1$ QCD. The Schr\"odinger functional scheme is used as the intermediate scheme to carry out non-perturbative running from the low…
In this paper we show that the apparent failure of QCD lattice perturbation theory to account for Monte Carlo measurements of perturbative quantities results from choosing the bare lattice coupling constant as the expansion parameter. Using…
We reanalyze the perturbative QCD (pQCD) corrections to quarkonium QCD sum rules and extract the heavy quark masses $\overline{m}_{q}(\overline{m}_{q})$ ($q=c,b$). At present, the pQCD corrections to the correlation functions of two…
We include the full second-order corrections to the static QCD potential in the analysis of the ttbar threshold cross section. There is an unexpectedly large difference between the QCD potential improved by the renormalization-group…
We demonstrate that sea quark effects of a magnitude expected from renormalization group considerations are clearly visible in the strong coupling constant measured in current full QCD simulations. Building on this result an estimate of…
It is conventional to choose a typical momentum transfer of the process as the renormalization scale and take an arbitrary range to estimate the uncertainty in the QCD prediction. However, predictions using this procedure depend on the…