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Related papers: The Small-x Behaviour of the Singlet Polarized Str…

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We report a semi-analytical approach for the solution of the nonlinear Gribov-Levin-Ryskin-Mueller-Qiu (GLR-MQ) evolution equation for sea quark distribution and investigate the effect of gluon shadowing on the small-x and moderate-Q^2…

High Energy Physics - Phenomenology · Physics 2018-08-09 Mayuri Devee

We study the small $x$ diffractive contribution to the spin--dependent proton structure function $g_1(x)$. We find that the $x\to 0$ behaviour of $ g_1(x)$ has a singular form like $1/(x^\alpha \ln^2(x))$ with $\alpha \sim 0.2-0.3$.

High Energy Physics - Phenomenology · Physics 2008-02-03 S. V. Goloskokov

Theoretical expectations concerning small $x$ behaviour of the spin dependent structure function $g_1$ are summarised. This includes discussion of the Regge pole model predictions and of the double $ln^2(1/x)$ effects implied by…

High Energy Physics - Phenomenology · Physics 2014-11-17 J. Kwiecinski

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

Nonsinglet structure function g_2(x) for deep inelastic scattering of a lepton on a constituent quark is calculated in the double logarithmic approximation at x<<1. Small-x asymptotics of g_2 is shown to have the same singular behaviour as…

High Energy Physics - Phenomenology · Physics 2007-05-23 B. I. Ermolaev , S. I. Troyan

The numerical effects of the known all-order leading and next-to-leading logarithmic small-$x$ contributions to the anomalous dimensions and coefficient functions of the unpolarized singlet evolution are discussed for the structure…

High Energy Physics - Phenomenology · Physics 2009-10-30 J. Blümlein , A. Vogt

We show that it is possible to use hard-Pomeron behavior to the gluon distribution and singlet structure function at low $x$. We derive a second-order independent differential equation for the gluon distribution and the singlet structure…

High Energy Physics - Phenomenology · Physics 2014-02-05 B. Rezaei , G. R. Boroun

The impact of the resummed next-to-leading logarithmic small-$x$ contributions to the anomalous dimension $\gamma_{gg}$ is evaluated for the unpolarized parton densities and structure functions of the nucleon. These new terms diminish the…

High Energy Physics - Phenomenology · Physics 2016-09-06 J. Blümlein , A. Vogt

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 gluon contributions to $F_L(x,Q^2)$ in ${\cal O}(\alpha_s)$ are calculated taking into account the transverse momentum of the initial state parton. In comparison with collinear factorization $F_L(x,Q^2)$, is not affected at large $x$…

High Energy Physics - Phenomenology · Physics 2009-10-28 Johannes Blümlein

We compute the structure function $g_2$ for a gluon target in perturbative QCD at order $\as$. We show that its first moment vanishes, as predicted by the Burkhardt-Cottingham sum rule.

High Energy Physics - Phenomenology · Physics 2009-10-30 A. Gabrieli , G. Ridolfi

We parametrize the small x, singlet component of the proton structure function F_2 by powers and logarithms of 1/x for discrete values of Q^2 between 0.2 and 2000 GeV^2, and compare these parametrizations by applying the criterion of…

High Energy Physics - Phenomenology · Physics 2009-10-31 P. Desgrolard , L. Jenkovszky , A. Lengyel , F. Paccanoni

We calculate the perturbative component of the DIS structure function F_1 singlet in the Double-Logarithmic Approximation (DLA) and account at the same time for the running QCD coupling effects. By constructing and solving evolution…

High Energy Physics - Phenomenology · Physics 2018-03-06 B. I. Ermolaev , S. I. Troyan

We make a critical study of the relationship between the singlet structure function $F_{2}^{S}$ and the gluon distribution $G(x,Q^{2})$ proposed in the past two decades, which is frequently used to extract the gluon distribution from the…

High Energy Physics - Phenomenology · Physics 2014-04-22 G. R. Boroun

We present calculation of F_L in the double-logarithmic approximation and demonstrate that the synergic effect of the factor 1/x from the \alpha_s^2-order and the steep x-dependence of the totally resummed double logarithmic contributions…

High Energy Physics - Phenomenology · Physics 2021-04-14 B. I. Ermolaev , S. I. Troyan

We have estimated the contributions to the moments of polarized nucleon structure function $g_1(x,Q^2)$ coming from the region of the very low x ($10^{-5}<x$). Our approach uses the nucleon structure function extrapolated to the region of…

High Energy Physics - Phenomenology · Physics 2014-11-17 B. Ziaja

Spin dependent structure function $g_1^{\gamma}(x,Q^2)$ of the polarised photon is analysed within the formalism based upon the unintegrated spin dependent parton distributions incorporating the LO Altarelli-Parisi evolution and the double…

High Energy Physics - Phenomenology · Physics 2014-11-17 J. Kwiecinski , B. Ziaja

A generalization of the leading-order DGLAP evolution at small x is performed for the non-singlet structure function by resumming the leading-order DGLAP anomalous dimension to all orders in the QCD coupling. Explicit expressions are…

High Energy Physics - Phenomenology · Physics 2010-03-25 B. I. Ermolaev , M. Greco , S. I. Troyan

We review recent developments in the theory and phenomenology of polarized structure functions. We summarize recent experimental data on the proton and deuteron structure function $g_1$, and their impact on the understanding of polarized…

High Energy Physics - Phenomenology · Physics 2008-02-03 Stefano Forte

We investigate shadowing corrections to the polarized deuteron structure functions g_1^d and b_1. In the kinematic domain of current fixed target experiments we observe that shadowing effects in g_1^d are approximately twice as large as for…

Nuclear Theory · Physics 2009-10-30 J. Edelmann , G. Piller , W. Weise