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Related papers: Parton Densitites at High-x

200 papers

Nuclear parton distribution functions are obtained by a chi^2 analysis of lepton deep inelastic experimental data. It is possible to determine valence-quark distributions at medium x and antiquark distributions at small x; however, the…

High Energy Physics - Phenomenology · Physics 2017-08-23 S. Kumano

Precise determinations of the strong coupling constant in hadronic collisions demand sets of parton densities spanning a sufficiently wide range of values for the QCD scale parameter Lambda. For such applications, we supplement the recent…

High Energy Physics - Phenomenology · Physics 2009-10-28 A. Vogt

We present a new analysis of parton distributions of the proton. This incorporates a wide range of new data, an improved treatment of heavy flavours and a re-examination of prompt photon production. The new set (MRST) shows systematic…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. D. Martin , R. G. Roberts , W. J. Stirling , R. S. Thorne

We report results of a new global next-to-leading order fit of parton distribution functions in which cuts on W and Q are relaxed, thereby including more data at high values of x. Effects of target mass corrections (TMCs), higher twist…

High Energy Physics - Phenomenology · Physics 2010-05-28 A. Accardi , M. E. Christy , C. E. Keppel , W. Melnitchouk , P. Monaghan , J. G. Morfin , J. F. Owens

The quantum statistical parton distributions approach proposed more than one decade ago is revisited by considering a larger set of recent and accurate Deep Inelastic Scattering experimental results. It enables us to improve the description…

High Energy Physics - Phenomenology · Physics 2015-12-09 Claude Bourrely , Jacques Soffer

We investigate the Q^2 evolution of parton distributions at small x values, recently obtained in the case of soft initial conditions. The results are in excellent agreement with deep inelastic scattering experimental data from HERA.

High Energy Physics - Phenomenology · Physics 2007-05-23 A. V. Kotikov , G. Parente

Recent analysis of proton and deuteron deep-inelastic scattering data have suggested that the extracted d/u quark distribution ratio at large x may be significantly larger than previously believed, if the data are corrected for nuclear…

High Energy Physics - Phenomenology · Physics 2011-02-01 W. Melnitchouk , J. C. Peng

The quantum statistical parton distributions approach proposed more than one decade ago is revisited by considering a larger set of recent and accurate Deep Inelastic Scattering experimental results. It enables us to improve the description…

High Energy Physics - Phenomenology · Physics 2015-10-22 Jacques Soffer , Claude Bourrely

We discuss the statistical properties of parton distributions within the framework of the NNPDF methodology. We present various tests of statistical consistency, in particular that the distribution of results does not depend on the…

After a brief recapitulation of the general interest of parton densities, we discuss multiple hard interactions and multiparton distributions. We report on recent theoretical progress in their QCD description, on outstanding conceptual…

High Energy Physics - Phenomenology · Physics 2015-06-03 Markus Diehl

The $Q^2$ evolution of polarised parton distributions at small $x$ is studied. Various analytic approximations are critically discussed. We compare the full evolution with that obtained from the leading-pole approximation to the splitting…

High Energy Physics - Phenomenology · Physics 2014-11-17 T. Gehrmann , W. J. Stirling

The determination of parton distribution functions in the nucleon and nuclei is important for obtaining precise hadron-reaction cross sections, from which any new exotic signature could be found. We show that a future neutrino factory could…

High Energy Physics - Phenomenology · Physics 2009-11-07 S. Kumano

We show that the off-diagonal (or skewed) parton distributions are completely determined at small $x$ and $\xi$ by the (conventional) diagonal partons. We present predictions which can be used to estimate the off-diagonal distributions at…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. G. Shuvaev , K. J. Golec-Biernat , A. D. Martin , M. G. Ryskin

Utilizing recent DIS measurements (F_{2,L}) and data on dilepton and high-E_{T} jet production we determine the dynamical parton distributions of the nucleon generated radiatively from valence-like positive input distributions at optimally…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Glück , P. Jimenez-Delgado , E. Reya

Collider data can play an important role in determining the parton distribution functions of the nucleon. I outline a formalism which makes it possible to use next-to-leading order calculations in such an extraction, while minimizing the…

High Energy Physics - Phenomenology · Physics 2009-10-30 David A. Kosower

The generalized parton distributions and the generalized distribution amplitudes give access to a deeper understanding of the quark and gluon content of hadrons. In this short review, we select some new developments of their interesting…

High Energy Physics - Phenomenology · Physics 2009-11-07 B. Pire

A study of the parameterization uncertainty at low Bjorken $x \le 0.1$ for the parton distribution functions of the proton is presented. The study is based on the HERA I combined data using a flexible parameterization form based on…

High Energy Physics - Phenomenology · Physics 2011-04-28 Alexander Glazov , Sven Moch , Voica Radescu

We critically examine uncertainties in parton distribution functions (PDFs) at large x arising from nuclear effects in deuterium F2 structure function data. Within a global PDF analysis, we assess the impact on the PDFs from uncertainties…

High Energy Physics - Phenomenology · Physics 2011-08-17 A. Accardi , W. Melnitchouk , J. F. Owens , M. E. Christy , C. E. Keppel , L. Zhu , J. G. Morfin

In this talk an introduction to generalized parton distributions is given. Recent developments are shortly reviewed, including non-perturbative calculations, phenomenological aspects and evaluation of higher order perturbative and power…

High Energy Physics - Phenomenology · Physics 2015-06-25 D. Müller

We provide an assessment of the state of the art in various issues related to experimental measurements, phenomenological methods and theoretical results relevant for the determination of parton distribution functions (PDFs) and their…