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Related papers: Structure Functions at Low x and Q2 at ZEUS

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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

Recent diffractive structure function measurements by the H1 and ZEUS experiments at HERA are reviewed. Various data sets, obtained using systematically different selection and reconstruction methods, are compared. NLO DGLAP QCD fits are…

High Energy Physics - Experiment · Physics 2007-05-23 Paul Newman , Frank-Peter Schilling

We summarise existing experimental and theoretical knowledge on the structure function $F_2$ in the region of low $Q^2$ and low $x$. The constraints on the behaviour of structure functions in the limit $Q^2=0$ are listed. Phenomenological…

High Energy Physics - Phenomenology · Physics 2009-09-25 Barbara Badelek , Jan Kwiecinski

The numerical study of QED radiative corrections in the low x region for the H1 experiment at HERA was performed. The analytical program TERAD91 was used to obtain the values of the radiative correction factor for the first measurement of…

High Energy Physics - Phenomenology · Physics 2008-07-18 A. A. Akhundov

Experimental data on the F2 structure functions of the proton and deuteron, including recent results from CLAS at Jefferson Lab, have been used to construct their n<=12 moments. A comprehensive analysis of the moments in terms of the…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Osipenko , W. Melnitchouk , S. Simula , S. Kulagin , G. Ricco , CLAS Collaboration

Recent data on the proton F_2 structure function in the resonance region suggest that local quark-hadron duality works remarkably well for each of the low-lying resonances, including the elastic, to rather low values of Q^2. We derive…

High Energy Physics - Phenomenology · Physics 2014-11-17 W. Melnitchouk

The photon structure function F_2^gamma has been measured at <Q^2> of 706 GeV^2, using a sample of two-photon events with a scattered electron observed in the OPAL electromagnetic endcap calorimeter. The data were taken during the years…

High Energy Physics - Experiment · Physics 2011-07-19 R. J. Taylor

The isoscalar structure functions xF_3 and F_2 are measured as functions of x averaged over all Q^2 permissible for the range 6 to 28 GeV of incident (anti)neutrino energy. With the measured values of xF_3, the value of the Gross-Llewellyn…

High Energy Physics - Experiment · Physics 2008-02-03 JINR Neutrino Detector Collaboration , L. S. Barabash et al

HERA has provided a wealth of high precision structure function and jet production data, allowing considerable progress to be made in understanding the structure of the proton. In this paper, several of the most recent proton structure…

High Energy Physics - Experiment · Physics 2014-11-17 C. Gwenlan

In this paper, the proton structure function $F_2 ^p (x,Q^2)$ at small-$x$ is investigated using an analytical solution of the Balitsky-Kovchegov (BK) equation. In the context of the color dipole description of deep inelastic scattering…

High Energy Physics - Phenomenology · Physics 2024-03-21 Ranjan Saikia , Pragyan Phukan , Jayanta Kumar Sarma

We present the first measurement of the Q^2-dependence of the neutron spin structure function g_2^n at five kinematic points covering 0.57 (GeV/c)^2 <= Q^2 <= 1.34 (GeV/c)^2 at x~0.2. Though the naive quark-parton model predicts g_2=0,…

Nuclear Experiment · Physics 2008-11-26 K. Kramer

The reanalysis of all available world data on the longitudinal asymmetry A|| is presented. The proton structure function g1 was extracted within a unique framework of data inputs and assumptions. These data allowed for a reliable evaluation…

High Energy Physics - Experiment · Physics 2017-08-23 M. Osipenko , S. Simula , P. Bosted , V. Burkert , E. Christy , K. Griffioen , C. Keppel , S. Kuhn , G. Ricco

The measurement and QCD analysis of neutral and charged current cross sections at HERA are presented. For the kinematic range of four-momentum transfer Q^2 between approx. 1 GeV^2 and 30000 GeV^2 and Bjorken x between 0.0013 and 0.65 the…

High Energy Physics - Experiment · Physics 2007-05-23 Nicole Werner

The strikingly different high energy behaviours of real photoabsorption cross-sections with Q^2 = 0 and the low x proton structure function at large Q^2 are studied from a laboratory frame viewpoint, in which the x and Q^2 dependence…

High Energy Physics - Phenomenology · Physics 2009-10-30 G. Kerley , G. Shaw

It is shown that recent small-x measurements of the photon structure function F_2^{\gamma}(x,Q^2) by the LEP-OPAL collaboration are consistent with parameter-free QCD predictions at all presently accessible values of Q^2.

High Energy Physics - Phenomenology · Physics 2009-11-07 M. Gluck , E. Reya , I. Schienbein

Events with a final-state proton carrying a large fraction of the proton-beam momentum, x_L>0.6, and the square of the transverse momentum p_T^2 <0.5 GeV^2, have been studied in e^+p collisions with the ZEUS detector at HERA. Data with…

High Energy Physics - Experiment · Physics 2012-08-27 ZEUS Collaboration

We present an improved determination of the proton structure functions $F_{2}$ and $xF_{3}$ from the CCFR $\nu $-Fe deep inelastic scattering (DIS) experiment. Comparisons to high-statistics charged-lepton scattering results for $F_{2}$…

High Energy Physics - Experiment · Physics 2008-11-26 CCFR Collaboration , W. Seligman

New data, especially HERA measurements of the proton structure function at small $x$, allow the opportunity to improve our knowledge of the gluon and quark distribution functions. We perform a global analysis which incorporates these new…

High Energy Physics - Phenomenology · Physics 2009-07-09 A. D. Martin , R. G. Roberts , W. J. Stirling

Partonic structure of constituent quark (or{\it{valon}}) in the Next-to-Leading Order is used to calculate pion structure function. This is a further demonstration of the finding that the constituent quark structure is universal, and once…

High Energy Physics - Phenomenology · Physics 2009-11-10 Firooz Arash