Related papers: Renormalon-based resummation for B(D) Mesons
The renormalized mass of the bottom quark is calculated at the two loop level to order ${\cal O}(\alpha_s G_F M_t^2)$ in the $\msbar$ renormalization scheme. Different strategies for the computation are outlined. The result is applied to…
Recently, it has been shown that the concept of the pole mass of a heavy quark becomes ambiguous beyond perturbation theory, because of the presence of infrared renormalons. We argue that the predictions of heavy quark effective theory,…
The decay constants of the charmed heavy pseudoscalar D and D_s mesons are revisited within a recently developed novel approach to dispersive QCD sum rules which relies on an unprejudiced implementation of quark-hadron duality. The proposed…
We investigate the question of how tightly we can constrain the cosmological parameters by using the ``cosmic inversion'' method in which we directly reconstruct the power spectrum of primordial curvature perturbations, $P(k)$, from the…
The decay rates and spectroscopy of the $Q \bar Q$ $(Q \in c, b)$ mesons are computed in non-relativistic phenomenological quark antiquark potential of the type $V(r)=-\frac{\alpha_c}{r}+A r^{\nu}$, (CPP$_{\nu}$) with different choices…
We generalize the concept of Borel resummability and renormalons to a quantum field theory with an arbitrary number of fields and couplings, starting from the known notion based on the running coupling constants. An approach to identify the…
In this work, the renormalization of the second-order QCD is analyzed at one-loop level, including an arbitrary chromomagnetic factor and quark self-interactions, which are mass dimension four operators in this framework. The model is shown…
MSbar-like schemes in QCD have in general the running coupling which contains Landau singularities, i.e., singularities outside the timelike semi-axis, at low squared momenta. As a consequence, evaluation of the spacelike quantities, such…
Time-dependent renormalization was employed to derive a nonlinear quantum master equation (QME), in which the dynamics of a non-equilibrium fluctuation in an irrelevant system are fed back into that of a relevant one. In terms of…
We present a sum-rule extraction of the decay constants of heavy-light mesons from the two-point correlator of pseudoscalar currents. To this end, we compare the perturbative expansions for the correlator and the decay constant performed in…
We compute next-to-next-to-leading order QCD corrections to the partonic processes $b\to c \bar{u} d$ and $b\to c \bar{c} s$, which constitute the dominant decay channels in standard model predictions for $B$-meson lifetimes within the…
Effective coupling constant in quantum electrodynamics is investigated. A pole appears in the effective coupling constant for the space-like momentum if it is calculated by perturbation. The pole can be eliminated by the analytic…
D mesons serve as excellent probes of hot and/or dense strongly interacting matter. They can provide insight into the restoration of chiral symmetry. The chiral condensate as well as other chirally odd condensates, such as certain…
Methods of Borel integration to calculate the binding ground energies and mass of b-barb quarkonia are presented. The methods take into account the leading infrared renormalon structure of the "soft" binding energy E(s) and of the quark…
We study RI/MOM renormalization constants of bilinear quark operators for $N_f=4$ and the strong coupling constant for $N_f=2+1+1$ using Wilson twisted-mass fermions. We use the "egalitarian" method to remove H(4) hypercubic artifacts…
We present a method of calculating the bottonium mass M[Upsilon(1S)] = [2 mb + E(b barb)]. The binding energy is separated into the soft and ultrasoft components E(b barb)=[E(s)+E(us)] by requiring the reproduction of the correct residue…
We introduce a more general set of kinematic renormalization schemes than the original momentum (MOM) subtraction schemes of Celmaster and Gonsalves. These new schemes will depend on a parameter $\omega$ which tags the external momentum of…
The mass of the bottom quark and the strong coupling constant alpha_s are determined from QCD moment sum rules for the Upsilon system. Two analyses are performed using both the pole mass M_b as well as the mass m_b in the $\MSb$ scheme. In…
In QCD sum-rule methods, the fundamental field-theoretical quantities are correlation functions of composite operators that serve as hadronic interpolating fields. One of the challenges of loop corrections to QCD correlation functions in…
Semileptonic and nonleptonic decays of the B_c meson are studied in the framework of the relativistic quark model. The heavy quark expansion in inverse powers of the heavy (b,c) quark mass is used to simplify calculations while the light…