相关论文: Resummed corrections to the \rho parameter in the …
We construct hyperasymptotic expansions for the heavy quark pole mass regulated using the principal value (PV) prescription. We apply such hyperasymptotic expansions to the $B/D$ meson masses, and $\bar \Lambda $ computed in the lattice.…
I discuss and compare several approaches to higher-order calculations of top quark production. I study the relative effectiveness of the approaches in approximating the exact NNLO results for the top-pair total cross section and highlight…
This talk reports on various aspects of the divergence of perturbative expansions in the context of matching QCD onto heavy quark effective theory. Implications for exclusive and inclusive decays of heavy mesons are discussed.
It is shown that amplitude-based, exact resummation tames the un-cancelled IR divergences at O(alpha_s^2) in initial state radiation in QCD with massive quarks. Implications for precision predictions for LHC physics are discussed.
Reaching a theoretical accuracy in the prediction of the lightest MSSM Higgs-boson mass, M_h, at the level of the current experimental precision requires the inclusion of momentum-dependent contributions at the two-loop level. Recently two…
A systematic method of summing the corrections to the renormalon residue arising from higher order renormalons is discussed.
We determine to order alpha^3 in the quenched approximation the so-called residual mass in the lattice regularisation of the Heavy Quark Effective Theory. We follow a gauge-invariant strategy which exploits the fact that this mass term…
I discuss the weak scale threshold corrections in supersymmetric models. I describe the ``match and run" approximation to the threshold corrections and compare with the exact one-loop results. With explicit examples I show that in cases…
We study the scheme dependence of the two-loop expression for the $\rho$-parameter of the Standard Model in the heavy $t$-quark mass limit $m_{t} \gg m_{w}$. In the $\ms$-scheme the two-loop electroweak correction to the ${\cal…
We perform a study of infinite hadronic matter, finite nuclei and hypernuclei with an improved method of calculating the effective baryon mass. A detailed study of the predictions of the model is made in comparison with the available data…
We extend the investigation of the reparametrization invariance of Heavy Quark Effective Theory to O(1/m_Q^3). We show that to this order reparametrization invariance can only be maintained if the the reparametrization transformation is…
It is shown that conventional mass renormalization, when applied to photonic or gluonic corrections to unstable particle propagators, leads to non-convergent series in the resonance region. A solution of this problem, based on the concepts…
We present a method to non-perturbatively determine the parameters of the on-shell, $O(a)$-improved relativistic heavy quark action. These three parameters, $m_0$, $\zeta$, and $c_B=c_E$ are obtained by matching finite-volume, heavy-heavy…
It has been shown that the principle of maximum conformality (PMC) provides a systematic way to solve conventional renormalization scheme and scale ambiguities. The scale-fixed predictions for physical observables using the PMC are…
Perturbative calculations for processes involving heavy flavours can be carried out using two approaches: the massive and the massless schemes. These schemes can also be combined to leverage their respective strengths. Additionally, both…
The threshold scan at future lepton colliders is the most precise known method to determine the top quark mass (well below 100 MeV), a fundamental parameter of the Standard Model that co-determines the stability properties of the…
In this talk I review the calculation of the third order corrections to the heavy quarkonium spectrum in the nonrelativistic effective theory framework and its application to the phenomenology of top quark threshold production.
A new method to measure the mass of the top quark at the LHC is presented. This method uses lepton energy distribution and ideally does not depend on the velocity distribution of the top quark. We perform a simulation analysis of the top…
A summary of recent results obtained for higher-order corrections to precision observables in the Standard Model and the Minimal Supersymmetric Standard Model is given. In the Standard Model electroweak two-loop results valid for arbitrary…
We derive the one-loop effective action induced by a heavy top in models with an extended Higgs sector. We use the effective action to analyze the top corrections to the $\rho$ parameter and to the Higgs-gauge boson couplings. We show that…