相关论文: Target Mass Corrections to the Spin-dependent Stru…

The QCD effects of twist-4 operators on the first moment of nucleon spin-dependent structure function $g_1(x, Q^2 )$ are studied in the framework of operator product expansion and renormalization group method. We investigate the operator…

We examine the implications of several parameterizations of so-called target mass corrections (TMCs) for the physics of parity-violating deeply inelastic scattering (DIS), especially at high values of the momentum fraction x. We consider…

We prove that regulating infrared divergencies generates power (~1/(Q^2)^k) corrections to the spin structure function g_1 at small x and large Q^2. At the same time it leads to the corrections ~(Q^2)^k at small Q^2. We present the explicit…

Theoretical description of the spin dependent structure function g_1(x,Q^2) in the region of low values of x and Q^2 is presented. It contains the Vector Meson Dominance contribution and the QCD improved parton model suitably extended to…

I consider three-point functions of one protected and two unprotected twist-two operators with spin in N=4 SYM at weak coupling. At one loop I formulate an empiric conjecture for the dependence of the corresponding structure constants on…

We present a systematic analysis of the processes $e^+ ~e^- \rightarrow e^+ ~e^- X$ to study the polarised and unpolarised photon structure functions. The effect of target photon mass, which manifests itself as new singly polarised…

We compute the combined two and three loop order correction to the spin-spin correlation functions for the 2D Ising and q-states Potts model with random bonds at the critical point. The procedure employed is the renormalisation group…

We show at the example of the matrix element between pion states of a twist-2, non-singlet operator that Wilson twisted mass fermions allow to compute this phenomenologically relevant quantitiy at small pseudo scalar masses of O(270 MeV).…

We present a first study of gluonic twist-four corrections to the deep inelastic structure function F_2 at small x and small Q^2. The calculations are based upon the double logarithmic approximation of the coupled twist-four evolution…

The recent high statistics NMC data on the Tin to Carbon structure function ratio seems to indicate, for the first time, a significant $Q^2$ dependence, especially at small values of Bjorken $x$, $x < 0.05$, and $Q^2 > 1 GeV^2$. Pure…

Using the variational formula for operator product coefficients a method for perturbative calculation of the short-distance expansion of the Spin-Spin correlation function in the two dimensional Ising model is presented. Results of explicit…

We develop a formalism for the resummation of target mass corrections in off-forward two-photon amplitudes given by a chronological product of electromagnetic currents, arising in e.g. deeply virtual Compton scattering. The method is based…

A model-independent way of computing the mass corrections of vector-meson distribution amplitudes is given. The method is based on resummation of (next-to-)leading twist local operator.

We describe a systematic approach [1] to the calculation of kinematic corrections ~ t/Q^2, m^2/Q^2 in hard exclusive processes which involve momentum transfer from the initial to the final hadron state. As an example, the complete…

We investigate target mass effects in the unpolarized virtual photon structure functions $F_2^\gamma(x,Q^2,P^2)$ and $F_L^\gamma(x,Q^2,P^2)$ in perturbative QCD for the kinematical region $\Lambda^2 \ll P^2 \ll Q^2$, where $-Q^2(-P^2)$ is…

We calculate the volume corrections to the two-pion matrix element of twist two operators.

We calculate the effects of the target mass on deep-inelastic electron scattering on targets of spin one such as the deuteron, focusing on the novel structure functions that enter. It is important to understand these effects given the…

Theoretical expectations concerning the low $x$ and low $Q^2$ behaviour of $g_1$ are summarized and compared with the recent SMC data.

Matrix elements of spin-dependent twist-four operators are extracted from recent data on the spin-dependent g_1 structure function of the proton and deuteron in the resonance region. We emphasize the need to include the elastic…

We have obtained a general solution of evolution equations for QCD twist-2 string operators in form of expansion over complete set of orthogonal eigenfunctions of evolution kernels in coordinate-space representation. In the leading…