Related papers: On the 1/Q correction to the C-parameter at two lo…
We compute the effective hamiltonian for non-leptonic |Delta F| = 1 decays in the standard model including next-to-next-to-leading order QCD corrections. In particular, we present the complete three-loop anomalous dimension matrix…
The increasing accuracy of current and planned experiments to measure the anomalous magnetic moment of the muon requires more precision and reliability of its theoretical calculation. For this purpose, we calculate the differential cross…
General one-loop contributions to the decay amplitudes $H\rightarrow \nu_l\bar{\nu}_l\gamma$ are presented, considering all possible contributions of additional heavy vector gauge bosons, fermions, and charged (and also neutral) scalar…
The renormalon calculus is used to calculate the terms of order $\beta_0^{n-1}\alpha_s^n$ in the perturbative expansions of the Wilson coefficients and hard-scattering kernels entering the QCD factorization formula for hadronic B-meson…
In the supersymmetric extension of the Standard Model we derive the two-loop QCD corrections to the scalar quark contributions to the electroweak precision observables entering via the rho parameter. A very compact expression is derived for…
We describe a general analytic-numerical reduction scheme for evaluating any 2-loop diagrams with general kinematics and general renormalizable interactions, whereby ten special functions form a complete set after tensor reduction. We…
We evaluate ABJM observables at two loops, for any value of the rank N of the gauge group. We compute the color subleading contributions to the four-point scattering amplitude in ABJM at two loops. Contrary to the four dimensional case, IR…
We compute the Darwin operator contribution ($1/m_b^3$ correction) to the width of the inclusive non-leptonic decay of a $B$ meson ($B^+$, $B_d$ or $B_s$), stemming from the quark flavour-changing transition $b \to q_1 \bar q_2 q_3$, where…
Closed expressions are presented for the contributions to QCD non-singlet forward evolution kernels $P(z)$ for the DGLAP equation and to $V(x,y)$ for non-forward (ER-BL) evolution equation for a certain class of diagrams which include…
Recently two-loop electroweak corrections to the neutral current four-fermion processes at high energies have been presented. The basic ingredient of this calculation is the evaluation of the two-loop corrections to the Abelian vector form…
We demonstrate that the results of the complete first order calculation of the non-factorizable QED corrections to the single-inclusive cross-sections for $e^+e^- \to W^+W^- \to 4$ fermions could be very well reproduced by a simple…
The $\b$ decay does not receive any nonspectator contributions and hence its theoretical calculation is relatively clean. Two different methods are employed for the study of $\b$. In the first method, both $b$ and $s$ quarks are treated as…
In calculating electroweak radiative corrections at two-loop level, one encounters Feynman graphs with several different masses on the internal propagators and on the external legs, which lead to complicated scalar functions. We describe a…
It has been shown that the one-loop behavior of the axial anomaly, occurring when the axial current is appropriately normalized, leads to the cancellation of the corrections of type $C_F^N{\bar \alpha}_s^N,~~ (N\geq 1) $ in the Crewther…
We compute the next-to-next-to-leading order (NNLO) QCD corrections to the six most important event shape variables related to three-particle final states in electron-positron annihilation. The corrections are sizeable for all variables,…
Two-loop electroweak corrections to the electron, muon, and tau lepton anomalous magnetic moments have been computed recently. Effects of hadronic contributions to the photon propagator in two-loop QED corrections have also been reanalysed.…
We calculate the non-singlet, the pure singlet contribution, and their interference term, at $O(\alpha^2)$ due to electron-pair initial state radiation to $e^+ e^-$ annihilation into a neutral vector boson in a direct analytic computation…
This paper presents a new method of numerical computation of the QED contributions to the electron anomalous magnetic moment which arises from Feynman graphs containing electron and photon lines and not containing electron loops. The method…
We calculate the one-loop electroweak corrections to e+e- to WWZ and e+e- to ZZZ and analyse their impacts on both the total cross section and some key distributions. These processes are important for the measurements of the quartic…
Analytic formulae are presented for the two-loop perturbative QCD corrections to b -> c decay at the zero recoil point, which are required for the extraction of |V_bc| from measurements of exclusive B -> D* l nu decays. The results are in…