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Related papers: Towards precision determination of uPDFs

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In this talk, we revisit inclusive DIS in the small $x$ limit and derive a new factorization formula that accounts for leading powers in both Bjorken and Regge limits. In this semi-classical description, we obtain a new unintegrated gluon…

High Energy Physics - Phenomenology · Physics 2021-10-06 Yacine Mehtar-Tani

The parton densities of the proton are of fundamental importance not only for our description of hadronic and nuclear structure, but also for reliable predictions for new heavy particle searches at colliders. At the large partonic momentum…

High Energy Physics - Phenomenology · Physics 2013-11-08 M. Brandt , M. Klasen

The gluon content of the proton, in the high-energy regime, is embodied by the unintegrated gluon distribution (UGD), which describes the gluon emission probability, with a given longitudinal momentum fraction and transverse momentum. The…

High Energy Physics - Phenomenology · Physics 2019-02-13 Andrèe Dafne Bolognino , Francesco Giovanni Celiberto , Dmitry Yu. Ivanov , Alessandro Papa

We derive analytical results for unintegrated color dipole gluon distribution function at small transverse momentum. By Fourier transforming the $S$-matrix for large dipoles we derive the results in the form of a series of Bells…

High Energy Physics - Phenomenology · Physics 2018-03-21 Raktim Abir , Khatiza Banu , Trambak Bhattacharyya , Mariyah Siddiqah , Nahid Vasim

We calculate the rate for the deep-inelastic electroproduction of dijets at HERA. We study the weakening of the azimuthal (back-to-back) correlation between the jets, as $x$ decreases, to see whether it can be used to identify BFKL dynamics…

High Energy Physics - Phenomenology · Physics 2009-10-28 A. J. Askew , D. Graudenz , J. Kwiecinski , A. D. Martin

Two-jet production from the direct photon contribution at HERA is a sensitive measure of the small-$x$ gluon in the proton. We propose measurements of ratios of the jet cross-sections which will clearly distinguish between gluons with or…

High Energy Physics - Phenomenology · Physics 2008-11-26 JR Forshaw , RG Roberts

We present for first time the computation at large $q_T$ (or small $b_T$) matching coefficients of Transverse Momentum Dependent Parton Distribution Function (TMDPDF) for linearly polarised to the integrated gluon distribution at…

High Energy Physics - Phenomenology · Physics 2019-08-19 Daniel Gutierrez-Reyes , Sergio Leal Gómez , Ignazio Scimemi , Alexey Vladimirov

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

The gluon distribution is obtained from the Golec-Biernat-W$\ddot{\mathrm{u}}$sthoff (GBW) and Bartels, Golec-Biernat and Kowalski (BGK) models at low $x$. We derive analytical results for the unintegrated color dipole gluon distribution…

High Energy Physics - Phenomenology · Physics 2025-09-24 G. R. Boroun

We present the first unbiased determination of spin-dependent, or polarized, Parton Distribution Functions (PDFs) of the proton. A statistically sound representation of the corresponding uncertainties is achieved by means of the NNPDF…

High Energy Physics - Phenomenology · Physics 2014-03-04 Emanuele Roberto Nocera

We present exploratory studies of the proton structure via two distinct kinds of gluon densities: the transverse-momentum dependent functions, whose evolution is determined by the CSS equation, and the unintegrated gluon distribution, whose…

High Energy Physics - Phenomenology · Physics 2022-10-18 Francesco Giovanni Celiberto

The H1 and Zeus collaborations have measured the inclusive diffractive DIS cross section ep -> eXp and these measurements are in good agreement within a normalisation uncertainty. Diffractive parton density functions (DPDFs) have been…

High Energy Physics - Experiment · Physics 2008-10-16 Paul Laycock

Collinear and transverse momentum dependent (TMD) parton densities are obtained from fits to precision measurements of deep inelastic scattering (DIS) cross sections at HERA. The parton densities are evolved by DGLAP evolution with…

High Energy Physics - Phenomenology · Physics 2019-04-17 A. Bermudez Martinez , P. Connor , F. Hautmann , H. Jung , A. Lelek , V. Radescu , R. Zlebcik

In high density QCD the hadron production stems from decay of mini-jets that have the transverse momenta of the order of the saturation scale. It is shown in this paper that this idea is able to describe in a unique fashion both the…

High Energy Physics - Phenomenology · Physics 2010-08-02 Eugene Levin , Amir H. Rezaeian

The imbalance of dijets produced in hadronic collisions has been used to extract the average transverse momentum of partons inside the hadrons. In this paper we discuss new contributions to the dijet imbalance that could complicate or even…

High Energy Physics - Phenomenology · Physics 2009-12-15 Daniel Boer , Piet J. Mulders , Cristian Pisano

We calculate the cross section of beauty production in electron-proton deep inelastic scattering at HERA collider in the framework of the kt-factorization approach. The unintegrated gluon distributions in a proton are obtained from the full…

High Energy Physics - Phenomenology · Physics 2011-03-23 A. V. Lipatov , N. P. Zotov

A feasibility study to extract the polarised gluon density from di-jet events at HERA in next-to-leading order is presented. It is shown that when taking next-to-leading order effects into account the asymmetries at HERA remain measurable…

High Energy Physics - Phenomenology · Physics 2007-05-23 G. Radel , A. De Roeck

The H1 and ZEUS Collaborations have performed new next-to-leading order QCD analyses to determine the parton density functions of the proton. QCD fits are performed using inclusive neutral and charged deep inelastic scattering cross…

High Energy Physics - Experiment · Physics 2017-08-23 C. Gwenlan

The production of hard di-jet events in photoproduction at HERA is dominated by resolved photon processes in which a parton in the photon with momentum fraction x_gamma is scattered from a parton in the proton. These processes are sensitive…

High Energy Physics - Experiment · Physics 2008-11-26 H1 Collaboration , C. Adloff

We present new parton distribution functions (PDFs) at next-to-leading order (NLO) and next-to-next-to-leading order (NNLO) in perturbative QCD, derived from a comprehensive global QCD analysis of high-precision data sets from combined HERA…

High Energy Physics - Phenomenology · Physics 2024-12-17 Majid Azizi , Maryam Soleymaninia , Hadi Hashamipour , Maral Salajegheh , Hamzeh Khanpour , Ulf-G. Meißner