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A. Kotikov

Publications and source records attributed to A. Kotikov.

8 recordsLinked to original sources

TMDlib2 and TMDplotter: a platform for 3D hadron structure studies

A common library, TMDlib2, for Transverse-Momentum-Dependent distributions (TMDs) and unintegrated parton distributions (uPDFs) is described, which allows for easy access of commonly used TMDs and uPDFs, providing a three-dimensional (3D) picture of the partonic structure of hadrons. The tool TMDplotter allows for web-based plotting of distributions implemented in TMDlib2, together with collinear pdfs as available in LHAPDF.

hep-ph

EMC effect at small Bjorken x values

The Bessel-inspired behavior of parton densities at small Bjorken x values is used along with `frozen' and analytic modifications of the strong coupling constant [1] to study the so-called EMC effect. Among other results, this approach allowed predicting small x behavior of the gluon density in nuclei.

hep-ph

Timelike small x Resummation for Fragmentation Functions

The status of small x resummation in the timelike kinematics is discussed. We present a general procedure to extract the large logarithms of x in the MS factorization scheme and to resum them in a closed form. New results for the doubly-logarithm-resummed coefficient functions will be reviewed. All our resummation formulae are in agrement with the fixed NNLO computations recently done by other groups in the \bar{MS} scheme.

hep-ph

Fully double-logarithm-resummed cross sections

We calculate the complete double logarithmic contribution to cross sections for semi-inclusive hadron production in the modified minimal-subtraction scheme by applying dimensional regularization to the double logarithm approximation. The full double logarithmic contribution to the coefficient functions for inclusive hadron production in electron-positron annihilation is obtained in this scheme for the first time. Our result agrees with all fixed order results in the literature, which extend to next-next-to-leading order.

hep-ph

Two-Loop Formfactors in Theories with Mass Gap and Z-Boson Production

The two-loop formfactor both for a U(1)xU(1) and a SU(2)xU(1) gauge theory with massive and massless gauge bosons respectively is evaluated at arbitrary momentum transfer q^2. The asymptotic behaviour for q^2->\infinity is compared to a recent calculation of Sudakov logarithms. The result is an important ingredient for the calculation of radiative corrections to Z-boson production at hadron and lepton colliders.

hep-ph

Ultra-high energy neutrino-nucleon interactions

Ultra-high energy ($E_ν>10^8 $ GeV) neutrino-nucleon total cross sections $σ^{νN}$ are estimated from a soft non-perturbative model complemented by an approximate QCD evolution, explicitly calculated. The resulting asymptotic energy behavior of the neutrino-nucleon charged-current total cross section is derived analytically and predictions concerning the observation of ultra-high energy neutrinos in future experiments are presented.

hep-ph

Small x Phenomenology: Summary and Status

The aim of this paper is to summarize the general status of our understanding of small x physics. It is based on presentations and discussions at an informal meeting on this topic held in Lund, Sweden, in March 2001. This document also marks the founding of an informal collaboration between experimentalists and theoreticians with a special interest in small x physics. This paper is dedicated to the memory of Bo Andersson, who died unexpectedly from a heart attack on March 4th, 2002.

hep-ph