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Related papers: Helicity Evolution at Small-x

200 papers

A next-to-leading order QCD calculation of non-singlet spin structure function, $g_{1}^{NS} $ is presented within the valon representation of Hadrons. In the valon model, it is assumed that a nucleon is composed of three dressed valence…

High Energy Physics - Phenomenology · Physics 2014-11-21 Fatemeh Taghavi Shahri , Firooz Arash

Saturation and geometrical scaling (GS) of gluon distributions are a consequence of the non-linear evolution equations of QCD. We argue that in pp GS holds for the inelastic cross-section rather than for the multiplicity distributions. We…

High Energy Physics - Phenomenology · Physics 2016-07-15 Michal Praszalowicz

Evolution of structure functions is studied in a chiral potential model which incorporates the pion as the chiral symmetry restoring field. Evolution equations for the quark and pion densities are derived in the lowest order at large $Q^2$.…

High Energy Physics - Phenomenology · Physics 2007-05-23 Kakali Roy-Maity , Padmanabha Dasgupta

We propose a matrix evolution equation in (x,kt)-space for flavour singlet, unintegrated quark and gluon densities, which generalizes DGLAP and BFKL equations in the relevant limits. The matrix evolution kernel is constructed so as to…

High Energy Physics - Phenomenology · Physics 2010-03-25 M. Ciafaloni , D. Colferai , G. P. Salam , A. M. Stasto

We provide the proper definition of all the leading-twist (un)polarized gluon transverse momentum dependent parton distribution functions (TMDPDFs), by considering the Higgs boson transverse momentum distribution in hadron-hadron collisions…

High Energy Physics - Phenomenology · Physics 2017-08-10 Miguel G. Echevarria , Tomas Kasemets , Piet J. Mulders , Cristian Pisano

We examine the QCD evolution of the helicity and transversity parton distribution functions when including also their dependence on transverse momentum. Using an appropriate definition of these polarized transverse momentum distributions…

High Energy Physics - Phenomenology · Physics 2015-06-15 Alessandro Bacchetta , Alexei Prokudin

We present results from two 1536^3 direct numerical simulations of rotating turbulence where both energy and helicity are injected into the flow by an external forcing. The dual cascade of energy and helicity towards smaller scales observed…

Fluid Dynamics · Physics 2015-05-14 P. D. Mininni , A. Pouquet

The Lange-Neubert evolution equation describes the scale dependence of the wave function of a meson built of an infinitely heavy quark and light antiquark at light-like separations, which is the hydrogen atom problem of QCD. It has numerous…

High Energy Physics - Phenomenology · Physics 2015-06-18 V. M. Braun , A. N. Manashov

This paper introduces a transverse-momentum dependent (TMD) factorization scheme designed to unify both large and small Bjorken-x regimes. We compute the next-to-leading order (NLO) quantum chromodynamics (QCD) corrections to the gluon TMD…

High Energy Physics - Phenomenology · Physics 2024-03-04 Swagato Mukherjee , Vladimir V. Skokov , Andrey Tarasov , Shaswat Tiwari

The perturbative QCD predictions concerning deep inelastic scattering at low $x$ are summarized. The theoretical framework based on the leading log $1/x$ resummation and $k_t$ factorization theorem is described and some recent developments…

High Energy Physics - Phenomenology · Physics 2010-03-25 J. Kwiecinski

We consider here the class of fully-nonlinear symmetry-integrable third-order evolution equations in 1+1 dimensions that were proposed recently in the journal Open Communications in Nonlinear Mathematical Physics, vol. 2, 216--228 (2022).…

Exactly Solvable and Integrable Systems · Physics 2024-08-07 Marianna Euler , Norbert Euler

We discuss the spin structure of the proton in a light-cone treatment of the chiral quark model. Based on the fact that the quark helicity ($\Delta q$) measured in polarized deep inelastic scattering experiments is actually the quark spin…

High Energy Physics - Phenomenology · Physics 2012-07-03 Xinyu Zhang , Bo-Qiang Ma

We use Lorentz invariance and the QCD equations of motion to study the evolution of functions that appear at leading order in a 1/Q expansion in azimuthal asymmetries. This includes the evolution equation of the Collins fragmentation…

High Energy Physics - Phenomenology · Physics 2009-11-07 A. A. Henneman , Daniel Boer , P. J. Mulders

Nonlinear evolution equation at small x with impact parameter dependence is analyzed numerically. Saturation scales and the radius of expansion in impact parameter are extracted as functions of rapidity. Running coupling is included in this…

High Energy Physics - Phenomenology · Physics 2015-03-17 Jeffrey Berger , Anna Stasto

Explicit expressions for the non-singlet and singlet structure functions g_1 in the small-x region are obtained. They include the total resummation of the double- and single- logarithms of x and account for the running QCD coupling effects.…

High Energy Physics - Phenomenology · Physics 2016-12-07 B. I. Ermolaev , M. Greco , S. I. Troyan

We perform the systematic numerical study of high vorticity structures that develop in the 3D incompressible Euler equations from generic large-scale initial conditions. We observe that a multitude of high vorticity structures appear in the…

Fluid Dynamics · Physics 2015-08-05 D. S. Agafontsev , E. A. Kuznetsov , A. A. Mailybaev

The DGLAP, BFKL, modified DGLAP and modified BFKL equations are constructed in a unified partonic framework. The antishadowing effect in the recombination process is emphasized, which leads to two different small $x$ behaviors of gluon…

High Energy Physics - Phenomenology · Physics 2007-05-23 Wei Zhu , Zhenqi Shen , Jifeng Yang , Jianhong Ruan

The Hamiltonian formulation of guiding-center Vlasov-Maxwell equations, which contain dipole contributions to the guiding-center polarization and magnetization, is presented in terms of a guiding-center Hamiltonian functional that is…

Plasma Physics · Physics 2024-10-04 Alain J. Brizard

The spin-dependent structure functions g_2 (x, Q^2) are investigated within the framework of the chiral quark soliton model. It turns out that the twist-3 part of g_2 (x, Q^2) gives nonnegligible contributions to the total distributions at…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Wakamatsu

The effect of the helicity on the dynamics of the turbulent flows is investigated. The aim is to disentangle the role of helicity in fixing the direction, the intensity and the fluctuations of the energy transfer across the inertial range…

Chaotic Dynamics · Physics 2016-02-09 Ganapati Sahoo , Fabio Bonaccorso , Luca Biferale