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Related papers: Spin-Dependent Structure Function g_1 at Small x

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The small $x$ behaviour of the structure function $h_1(x,Q^2)$ is studied within the leading logarithmic approximation of perturbative QCD. There are two contributions relevant at small $x$. The leading one behaves like $(\frac{1}{x})^0$…

High Energy Physics - Phenomenology · Physics 2007-05-23 R. Kirschner , L. Mankiewicz , A. Schäfer , L. Szymanowski

We generalize the Bartels-Ermolaev-Ryskin approach for the $g_1$ structure function at small-$x$ to determine the small-$x$ asymptotic behavior of the orbital angular momentum distributions in QCD. We present an exact analytical solution of…

High Energy Physics - Phenomenology · Physics 2019-09-04 Renaud Boussarie , Yoshitaka Hatta , Feng Yuan

The small-x behavior of the singlet contributions to the polarized structure function g_2(x,Q^2) is calculated in the double-logarithmic approximation of perturbative QCD. The dominant contribution is due to the gluons which, in contrast to…

High Energy Physics - Phenomenology · Physics 2009-11-07 J. Bartels , M. G. Ryskin

The explicit expressions for the non-singlet DIS structure functions obtained at small x by resumming the most singular logarithmic contributions are discussed and compared in detail with the DGLAP evolution for different values of x and…

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

Nonsinglet contributions to the $g_1(x,Q^2)$ structure function are calculated in the double-logarithmic approximation of perturbative QCD in the region $x \ll 1$. Double logarithmic contributions of the type $(\alpha_s \ln ^2 (1/x))^k$…

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

The structure function $g_1(x,Q^2)$ is analysed within the formalism based on unintegrated spin dependent parton distributions incorporating the LO Altarelli-Parisi evolution and the double $ln^2(1/x)$ resummation at low $x$. We…

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

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

It is shown in the framework of the operator product expansion and the renormalization group method that the twist-3 part of flavour nonsinglet spin structure function g_2(x,Q^2) obeys a simple Dokshitzer-Gribov- Lipatov-Altarelli-Parisi…

High Energy Physics - Phenomenology · Physics 2014-11-17 Ken Sasaki

The running of the QCD coupling is incorporated into the infrared evolution equations for the flavour structure function g_1. The explicit expressions for g_1 including the total resummation of the double-logarithmic contributions and…

High Energy Physics - Phenomenology · Physics 2008-11-26 B. I. Ermolaev , M. Greco , S. I. Troyan

The double logarithmic terms $\alpha_{s} \ln^{2}x $ are important to predict precisely the small $x$ behavior of the spin structure function $g_{1}$. We numerically analyze the evolution of the flavor non-singlet $g_{1}$ including the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Yuichiro Kiyo , Jiro Kodaira , Hiroshi Tochimura

The perturbative QCD predictions for the small $x$ behaviour of the nucleon structure functions $F_{2,L}(x,Q^2)$ and $g_1(x,Q^2)$ are summarized. The importance of the double logarithmic terms for the small $x$ behaviour of the spin…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. Kwiecinski

The proton spin dependent structure function $g_1^p$ is analysed using the unified scheme incorporating both Altarelli-Parisi evolution and the double $ln^2(1/x)$ effects at low $x$. The latter are found to be very important in the region…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. Kwiecinski , B. Ziaja

An alternative equation, resumming of the $\ln^2 1/x$ terms for the polarized nonsinglet structure function $g_1^{NS}$ at small $x$ is presented. Construction of the GLAP-like formula for the auxiliary function, corresponding to the…

High Energy Physics - Phenomenology · Physics 2011-03-17 Dorota Kotlorz , Andrzej Kotlorz

A unified equation for the non-singlet spin dependent structure function $g_1^{ns}(x,Q^2)$ which incorporates the complete leading order Altarelli-Parisi evolution at finite $x$ and double logarithmic $ ln^2(1/x)$ effects at $x \to 0$ is…

High Energy Physics - Phenomenology · Physics 2014-11-17 B. Badełek , J. Kwieciński

We examine the behaviour of the polarised structure function data for g_1(x) in the region of small x (~0.01 to 0.1) for the various available targets (proton, neutron and deuteron) with the aim of clarifying what may be safely deduced with…

High Energy Physics - Phenomenology · Physics 2007-05-23 Mehrdad Goshtasbpour , Philip G. Ratcliffe

The spin structure function $g_1^p$ of the proton is studied in a two component framework, where the perturbative evolution of parton distributions and nonperturbative vector meson dominance model are used. We predict the $g_1^p$ asymmetric…

High Energy Physics - Phenomenology · Physics 2015-03-10 Wei Zhu , Jianhong Ruan

The singlet contribution to the $g_1(x,Q^2)$ structure function is calculated in the double-logarithmic approximation of perturbative QCD in the region $x \ll 1$. Double logarithmic contributions of the type $(\alpha_s \ln ^2 (1/x))^k$…

High Energy Physics - Phenomenology · Physics 2014-11-17 J. Bartels , B. I. Ermolaev , M. G. Ryskin

Theoretical predictions show that at low values of Bjorken $x$ the spin structure function, $g_1$ is influenced by large logarithmic corrections, $ln^2(1/x)$, which may be predominant in this region. These corrections are also partially…

High Energy Physics - Phenomenology · Physics 2014-11-17 Beata Ziaja

We consider low-$x$ behaviour of the spin structure functions $g_1(x)$ and $h_1(x)$ in the unitarized chiral quark model which combines ideas on the constituent quark structure of hadrons with a geometrical scattering picture and unitarity.…

High Energy Physics - Phenomenology · Physics 2009-10-30 S. M. Troshin , N. E. Tyurin

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