Related papers: Pade/renormalization-group improvement of inclusiv…
Using renormalization-group methods, we derive differential equations for the all-orders summation of logarithmic corrections to the QCD series for R(s) = sigma(e^+ e^- --> hadrons)/sigma(e^+ e^- --> mu^+ mu^-), as obtained from the…
We study a rate asymmetry in the inclusive decay $\Bsgamma$, assuming the supersymmetric standard model based on N=1 supergravity. A complex coefficient $A$ for scalar-trilinear couplings is the source of CP violation, which is contained in…
The Cabibbo-Kobayashi-Maskawa matrix element $|V_{\rm cb}|$ is an important Standard Model parameter, whose value can be determined by using the semi-leptonic decay $B\rightarrow D^{*}\ell{\bar \nu}_\ell$. The perturbative QCD (pQCD)…
We compute the $\alpha_s^2 n_f$ perturbative QCD contribution to semileptonic B decay, including the finite mass of the charm quark. This result provides an estimate of the size of the two-loop correction, which is found to be about 50\% of…
We present upgraded theoretical predictions for inclusive and exclusive radiative decays of {\it B} mesons. Our results include those next-to-leading order corrections that have already been computed. Our best estimates in the Standard…
We set up a suitable renormalization programme for the one-loop computation of the decay rate Gamma(H==>hh) in the Minimal Supersymmetric extension of the Standard Model. We then perform an explicit diagrammatic calculation, including the…
We make a systematic investigation on the two-body nonleptonic decays $B_c\rightarrow J/\Psi(\eta_c),M$ by employing the perturbative QCD approach based on $k_T$ factorization, where $M$ is a light pseudoscalar or vector or a heavy charmed…
We introduce an optimal renormalization group analysis pertinent to the analysis of polarization functions associated with the $s$-quark mass relevant in $\tau$-decay. The technique is based on the renormalization group invariance…
The field-theoretical renormalization group approach in three dimensions is used to estimate the universal critical values of renormalized coupling constants g_6 and g_8 for the O(n)-symmetric model. The RG series for g_6 and g_8 are…
We present the partial branching fraction for inclusive charmless semileptonic B decays and the corresponding value of the CKM matrix element |Vub|, using a multivariate analysis method to access ~90% of the B -> Xu l nu phase space. This…
The time-dependent CP asymmetries in fully reconstructed B0 --> D(*)pi/rho decays (new preliminary result), and in partially reconstructed B0 --> D(*)pi decays, are measured with the BaBar detector at the PEP-II asymmetric B factory at…
The complete analysis of a model with three quartic coupling constants associated with an O(2N)--symmetric, a cubic, and a tetragonal interactions is carried out within the three-loop approximation of the renormalization-group (RG) approach…
We employ OPE techniques within HQET to calculate the inclusive semileptonic decays of polarized $\Lambda_b$ baryons. Lepton mass effects are included which enables us to also discuss rates into polarized $\tau$-leptons. We present explicit…
In the context of MSSM, a novel improving procedure based on the renormalization group equation is applied to the effective potential in the Higgs sector. We focus on the one-loop radiative corrections computed in Landau gauge by using the…
The $b \rightarrow s \gamma$, $b \rightarrow d \gamma$ and $b \rightarrow s \ell^+ \ell^-$ processes are allowed at higher order via the electroweak loop or box diagrams in the Standard model. It is sensitive probe to search for new physics…
Some recent Babar results on semileptonic decays are presented. They focus on the determination of the CKM matrix elements |V_{ub}| and |V_{cb}| in inclusive and exclusive b --> u l nu and b--> c l nu decays, and on form factors measurement…
The semi-analytical $O(\alpha_s^4)$ expression for the renormalization group $\beta$-function in the ${\rm{V}}$-scheme is obtained in the case of the $SU(N_c)$ gauge group. In the process of calculations we use the existing information…
Semileptonic decays of charged and neutral $B$ mesons play a critical role in the determination of the magnitudes of the CKM-matrix elements $V_{cb}$ and $V_{ub}$, and in the test of the lepton universality which is a basic assumption of…
We compute the renormalization of the complete CKM matrix in the MSbar scheme and perform a renormalization group analysis of the CKM parameters. The calculation is simplified by studying only the Higgs sector, which for the \beta-function…
Multi-scale renormalization group (RG) methods are reviewed and applied to the analysis of the effective potential for radiative symmetry breaking with multiple scalar fields, allowing an extension of the Gildener & Weinberg (GW) method…