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Related papers: The longitudinal structure function F_L: perturbat…

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We present approximations of varying degree of sophistication to the integral equations for the (gluon) structure functions of a hadron (``the partonic flux factor'') in a model valid in the Leading Log Approximation with a running coupling…

High Energy Physics - Phenomenology · Physics 2009-10-30 B. Andersson , G. Gustafson , H. Kharraziha

A precise proton structure function F_2 at low x is measured. The data is interpreted in the framework of QCD with an extraction of gluon density xg. The charm contribution to F_2 is determined in an extended kinematic range. Neutral and…

High Energy Physics - Phenomenology · Physics 2009-10-31 Zhiqing Zhang

We computed the deep inelastic scattering (DIS) structure functions $F_2 (x,Q^2)$ and $F_L (x,Q^2)$ in the framework of Gribov-Levin-Ryskin-Mueller-Qiu, Zhu-Ruan-Shen (GLR-MQ-ZRS) equation. Both $x$ and $Q^2$ evolutions of the structure…

High Energy Physics - Phenomenology · Physics 2019-10-01 Madhurjya Lalung , Pragyan Phukan , Jayanta Kumar Sarma

We present new sets of fragmentation functions in next-to-leading order QCD that are determined from e+e- annihilation data of inclusive particle production. In addition to the O(alpha_s) unpolarized cross section the longitudinal cross…

High Energy Physics - Phenomenology · Physics 2007-05-23 Janko Binnewies

We analyze the structure of generalized off-diagonal and transverse-momentum dependent quark-quark and gluon-gluon correlators for a spin-1/2 hadron. Using the light-front formalism, we provide a parametrization in terms of the parton…

High Energy Physics - Phenomenology · Physics 2015-06-16 C. Lorcé , B. Pasquini

The next-to-next-to-leading order (NNLO) QCD analysis is performed for the virtual photon structure functions which can be measured in the double-tag events in two-photon processes in $e^+e^-$ collisions. We investigate the perturbative QCD…

High Energy Physics - Phenomenology · Physics 2008-12-30 Ken Sasaki , Takahiro Ueda , Yoshio Kitadono , Tsuneo Uematsu

We present the calculation of the order $\alpha_s^2$ corrections to the coefficient functions contributing to the longitudinal ($F_L(x,Q^2)$) and transverse fragmentation functions ($F_T(x,Q^2)$) measured in electron-positron annihilation.…

High Energy Physics - Phenomenology · Physics 2009-09-25 P. J. Rijken , W. L. van Neerven

New Results on the measurement of the proton structure function F_2(x,Q^2) are reported for momentum transfers squared Q^2 >= 1.5 GeV^2 and Bjorken x >= 3.5 10^{-5} using data collected by the HERA experiments H1 and ZEUS in 1994. F_2…

High Energy Physics - Experiment · Physics 2007-05-23 Gregorio Bernardi

I calculate the longitudinal structure function, using Laplace transform techniques, from the parametrization of the structure function $F_{2}(x,Q^{2})$ and its derivative at low values of the Bjorken variable $x$. I consider the effect of…

High Energy Physics - Phenomenology · Physics 2022-02-01 G. R. Boroun

In the present contribution, we study the Landau-Lifshitz-Gilbert equation with two versions of structural derivatives recently proposed: the scale $q-$derivative in the non-extensive statistical mechanics and the axiomatic metric…

Mathematical Physics · Physics 2017-05-17 José Weberszpil , José Abdalla Helayël-Neto

We report on the extension of the data fitting considering the QCD inspired model based on the summation of gluon ladders applied to the $ep$ scattering. In lines of a two Pomeron approach, the structure function $F_2$ has a hard piece…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Lengyel , M. V. T. Machado

We study the analytic structure of light-front wave functions (LFWFs) and its consequences for hadron form factors using an explicitly Lorentz-invariant formulation of the front form. The normal to the light front is specified by a general…

High Energy Physics - Phenomenology · Physics 2009-09-11 S. J. Brodsky , J. R. Hiller , D. S. Hwang , V. A. Karmanov

We investigate 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 the mass squared of the probe…

High Energy Physics - Phenomenology · Physics 2008-11-26 T. Ueda , K. Sasaki , T. Uematsu

Possibilities for the measurement of the longitudinal structure function in diffraction $F_\mathrm{L}^\mathrm{D}$ at the future US Electron Ion Collider are investigated. The sensitivity to $F_\mathrm{L}^\mathrm{D}$ arises from the…

High Energy Physics - Phenomenology · Physics 2022-04-27 Nestor Armesto , Paul R. Newman , Wojciech Slominski , Anna M. Stasto

The present knowledge of the structure of the photon is presented based on results obtained by measurements of photon structure functions at e+e- collider. Results are presented both for the QED structure of the photon as well as for the…

High Energy Physics - Experiment · Physics 2009-07-17 Richard Nisius

We obtain an approximate analytical form of the gluon distribution using the GLAP equation with a factorization ansatz,and test its validity by comparing it with that of Gluck,Reya and Vogt at low $x$ regime. We also present calculations of…

High Energy Physics - Phenomenology · Physics 2014-11-17 Ranjita Deka , D. K. Choudhury

This paper addresses estimation in a longitudinal regression model for association between a scalar outcome and a set of longitudinally-collected functional covariates or predictor curves. The framework consists of estimating a time-varying…

Applications · Statistics 2020-06-30 Madan G. Kundu , Jaroslaw Harezlak , Timothy W. Randolph

Fragmentation functions are determined for the pion, kaon, and proton by analyzing charged-hadron production data in electron-positron annihilation. It is important that uncertainties of the determined fragmentation functions are estimated…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. Hirai , S. Kumano , T. -H. Nagai , K. Sudoh

Results are presented of two studies addressing the scaling violations of deep-inelastic structure functions. Factorization-scheme independent fits to all ep and mu p data on F_2 are performed at next-to-leading order (NLO), yielding…

High Energy Physics - Phenomenology · Physics 2009-10-31 Andreas Vogt

We present consistently ordered calculations of the structure functions F_2(x,Q^2) and F_L(x,Q^2), in different expansion schemes. After discussing the standard expansion in powers of alpha_s(Q^2) we consider a leading-order expansion in…

High Energy Physics - Phenomenology · Physics 2008-11-26 R. S. Thorne