Related papers: Complete three-loop QCD corrections to leptonic wi…
We present the three-loop calculations of the nonrelativistic QCD (NRQCD) current renormalization constants and corresponding anomalous dimensions, and the matching coefficients for the spatial-temporal tensor and spatial-spatial…
We study $J/\psi$ and $\eta_c$ inclusive production in $\Upsilon$ decay within the framework of nonrelativistic-QCD (NRQCD) factorization. In the latter case, for which no experimental data exist so far, we also include the $h_c$ feed-down…
The QCD radiative corrections to the leptonic decay rate of the $B_c$ meson are calculated using the formalism of nonrelativistic QCD (NRQCD) to separate short-distance and long-distance effects. The $B_c$ decay constant is factored into a…
We calculate the one-loop QCD corrections to $t\rightarrow \tilde t_1 \tilde \chi^0_j$ using dimensional reduction scheme, including QCD and supersymmetric QCD corrections. The analytic expressions for the corrections to the decay width are…
In this paper, we investigate the decay of Higgs boson to $J/\psi(\Upsilon)$ plus a photon based on NRQCD factorization. For the direct process, we calculate the decay width up to QCD NLO. We find that the decay width for process $H \to…
We present results for two-loop QCD corrections to the short distance coefficient that governs leptonic decay of Bc-meson. After brief discussion of the technics of asymptotic threshold expansion used to perform this calculation, we give…
In this work, we study the exclusive decay of $\Upsilon$ into $J/\psi$ in association with $\eta_c$ ($\chi_{c0,1,2}$). The decay widths for different helicity configurations are evaluated up to QCD next-to-leading order within the…
We present the first full analytic results of next-to-next-to-leading order (NNLO) QCD corrections to the top-quark decay width $\Gamma(t\to Wb)$ by calculating the imaginary part of three-loop top-quark self-energy diagrams. The results…
In this work, we determine the short-distance coefficients for $\Upsilon$ inclusive decay into a charm pair through relative order $v^4$ within the framework of NRQCD factorization formula. The short-distance coefficient of the order-$v^4$…
We compute one-loop QCD corrections to the triple differential width of the inclusive decay $\bar{B} \to X_c \ell \bar{\nu}_\ell$ including contributions from all relevant dimension-six operators in the Weak Effective Theory (WET), at…
In this paper, we study the $J/\psi(\Upsilon)$ production in Z boson decay in color-singlet model(CSM). We calculate the next-to-leading-order (NLO) QCD correction to $Z \to Quarkonium+Q\bar{Q}$, the dominant contribution in the CSM, with…
We propose to resum exactly any number of one-loop vacuum polarization insertions into the scale of the coupling of lowest order radiative corrections. This makes maximal use of the information contained in one-loop perturbative corrections…
We compute corrections of order $\alpha_s^3$ to the decay $b \to c \ell \bar\nu$ taking into account massive charm quarks. In the on-shell scheme large three-loop corrections are found. However, in the kinetic scheme the three-loop…
We calculate the one-loop QCD corrections for the decay of an off-shell vector boson with vector couplings into two pairs of quarks of equal or unequal flavours keeping all orders in the number of colours. These matrix elements are relevant…
Non-relativistic QCD (NRQCD) is used to calculate the relativistic correction to the amplitude for exclusive photoproduction of vector Quarkonia in the near-threshold region within the generalized parton distribution (GPD) framework. The…
We present an analytical calculation of the two-loop QCD corrections to the electromagnetic form factor of heavy quarks. The two-loop contributions to the form factor are reduced to linear combinations of master integrals, which are…
It has been a long-standing problem that the rare electromagnetic decay process $J/\psi\to 3\gamma$ is plagued with both large and negative radiative and relativistic corrections. To date it remains futile to make a definite prediction to…
We calculate the cross section for hadroproduction of a pair of heavy quarks in a 3S1 color-singlet state at next-to-leading order in QCD. This corresponds to the leading contribution in the NRQCD expansion for J/psi and Upsilon production.…
We evaluate in the framework of QCD factorization the two-loop vertex corrections to the decays $\bar{B}_{(s)}\to D_{(s)}^{(\ast)+} \, L^-$ and $\Lambda_b \to \Lambda_c^+ \, L^-$, where $L$ is a light meson from the set…
We update the study of the QCD corrections to direct J/psi and Upsilon hadroproduction in association with a photon in the QCD-based approach of the Colour-Singlet (CS) Model. After comparison with the recent full next-to-leading-order…