Related papers: Vector Correlator in Massless QCD at Order O(alpha…
The spectral function related to the correlator of two colour-electric fields along a Polyakov loop determines the momentum diffusion coefficient of a heavy quark near rest with respect to a heat bath. We compute this spectral function at…
We discuss Pad\'e-improvement of known four-loop order results based upon an asymptotic three-parameter error formula for Pad\'e-approximants. We derive an explicit formula estimating the next-order coefficient $R_4$ from the previous…
Coherent electroproduction of vector mesons off $^2$H and $^4$He is considered in the kinematics of deep inelastic scattering. Special emphasis is given to the $-t\sim 0.8-1$ GeV$^2$ region where the cross section is dominated by the…
We show in a model independent way the equality of the branching fractions and strong phases for B-> D_1M and B-> D_2^*M at leading order in Lambda _{QCD}/Q and alpha_s(Q) where Q={m_b,m_c,E_M} and M is a light meson. These results apply in…
We consider the correlator <W_n O(x)> of a light-like polygonal Wilson loop with n cusps with a local operator (like the dilaton or the chiral primary scalar) in planar N =4 super Yang-Mills theory. As a consequence of conformal symmetry,…
In order to study the fate of mesons in thermal QCD at finite baryon chemical potential, we consider light mesonic correlation functions using the Taylor expansion to ${\cal O}((\mu/T)^2)$, in both the hadronic and quark-gluon plasma…
So far no theoretical tool for the comprehensive description of exclusive electroproduction of vector mesons off nuclei at medium energies has been developed. We suggest a light-cone QCD formalism which is valid at any energy and…
We calculate the next-to-leading order(NLO) quantum chromodynamics(QCD) corrections to the inclusive process of $Z_0 \rightarrow B^*_c+\bar{c}+b$ under the non-relativistic QCD(NRQCD) factorization scheme. Technical details about…
We consider the Z Q Qbar vertex to second order in the QCD coupling for an on-shell massive quark-antiquark pair and for arbitrary momentum transfer of the Z boson. We present closed analytic expressions for the two parity-violating form…
We study $\bar qq$-hybrid mixing for the light vector mesons and $\bar qq$-glueball mixing for the light scalar mesons in Monte-Carlo based QCD Laplace sum rules. By calculating the two-point correlation function of a vector $\bar…
We derive the QCD corrections to the electroweak gauge bosons vacuum polarization functions at high and zero--momentum transfer in the case of arbitrary internal quark masses. We then discuss in this general case (i) the connection between…
We study the signal of dark matter and photon associated production induced by the vector and axial-vector operators at the LHC, including the QCD next-to-leading order (NLO) effects. We find that the QCD NLO corrections reduce the…
We improve the non-relativistic QCD (NRQCD) action by comparing the dispersion relation to that of the continuum through $\mathcal{O}(p^6)$ in perturbation theory. The one-loop matching coefficients of the $\mathcal{O}(p^4)$ kinetic…
In the virtual presence of a heavy quark t, the interactions of a CP-odd scalar boson A, with mass M_A << 2M_t, with gluons and light quarks can be described by an effective Lagrangian. We analytically derive the coefficient functions of…
The effects of electron correlation in the quasi-two-dimensional organic conductor \alpha-(BEDT-TTF)2I3 are investigated theoretically by using an extended Hubbard model with on-site and nearest-neighbor Coulomb interactions. A variational…
Recent developements in the calculation of the NNLO QCD corrections to the charm quark mass dependent matrix elements in B -> X_s gamma are reported. Special emphasis is put on the new results of the virtual O(alpha_s^2) fermionic…
The QCD$\times$QED factorization is studied for two-body non-leptonic and semi-leptonic $B$ decays with heavy-light final states. These non-leptonic decays, like $\bar{B}^0_{(s)}\to D^+_{(s)} \pi^-$ and $\bar{B}_d^0 \to D^+ K^-$, are among…
We derive the analytic expression for the one-loop $SU(N_{c})$ QCD effective potential including $N_{f}$ flavor quarks which non-linearly interact with the chromo-magnetic background field and the external $U(1)_{em}$ magnetic field. After…
The leading perturbative contributions into the two-point gauge-invariant correlator $Tr<gF(x)U(x,0)U(0,y)F(y)U(y,0)U(0,x)>$ are calculated at the one-loop order. It is shown, that nonlocal condensate is nonzero at this order. The relation…
In the framework of analytic approach to QCD, which has been recently intensively developed, the dependence of nonperturbative contributions in a running coupling of strong interaction on initial perturbative approximation to 3-loop order…