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Related papers: Updates of PDFs in the MMHT framework

200 papers

We formulate a general approach to the inclusion of theoretical uncertainties, specifically those related to the missing higher order uncertainty (MHOU), in the determination of parton distribution functions (PDFs). We demonstrate how,…

Without proper control of numerical and methodological errors in theoretical predictions at the per mille level it is not possible to study the effect of input parameters in current hadron-collider measurements at the required precision. We…

High Energy Physics - Phenomenology · Physics 2020-01-07 John Campbell , Tobias Neumann

We present a new QCD analysis of parton distribution functions (PDFs) at the next-to-leading order (NLO) and next-to-next-to-leading order (NNLO). In the present paper, the role of special types of experimental measurements for extracting…

High Energy Physics - Phenomenology · Physics 2024-05-20 Majid Azizi , Ali Khorramian , Saeid Paktinat Mehdiabadi

We construct a set of parton distribution functions (PDFs) in which fixed-order NLO and NNLO calculations are supplemented with soft-gluon (threshold) resummation up to NLL and NNLL accuracy respectively, suitable for use in conjunction…

High Energy Physics - Phenomenology · Physics 2015-10-13 Marco Bonvini , Simone Marzani , Juan Rojo , Luca Rottoli , Maria Ubiali , Richard D. Ball , Valerio Bertone , Stefano Carrazza , Nathan P. Hartland

We perform a comprehensive analysis of the strange-antistrange parton distribution function (PDF) asymmetry in the proton in the framework of chiral effective theory, including the full set of lowest order kaon loop diagrams with off-shell…

High Energy Physics - Phenomenology · Physics 2016-12-21 X. G. Wang , Chueng-Ryong Ji , W. Melnitchouk , Y. Salamu , A. W. Thomas , P. Wang

We present a new set of parton distribution functions (PDFs) based on a fully global dataset and machine learning techniques: NNPDF4.0. We expand the NNPDF3.1 determination with 44 new datasets, mostly from the LHC. We derive a novel…

We present a new set of parton distributions, NNPDF3.1, which updates NNPDF3.0, the first global set of PDFs determined using a methodology validated by a closure test. The update is motivated by recent progress in methodology and available…

We report on recent determinations of NNLO parton distributions and of $\alpha_s(M_Z)$ based on the world deep-inelastic data, supplemented by collider data. Some applications are discussed for semi-inclusive processes at the LHC.

High Energy Physics - Phenomenology · Physics 2013-03-19 S. Alekhin , J. Blümlein , S. Moch

We determine a new set of parton distribution functions (ABMP16), the strong coupling constant $\alpha_s$ and the quark masses $m_c$, $m_b$ and $m_t$ in a global fit to next-to-next-to-leading order (NNLO) in QCD. The analysis uses the…

High Energy Physics - Phenomenology · Physics 2017-07-26 S. Alekhin , J. Blümlein , S. Moch , R. Placakyte

We present a new set of parton distributions obtained at NNLO. These differ from the previous sets available at NNLO due to improvements in the theoretical treatment. In particular we include a full treatment of heavy flavours in the region…

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

We present NNPDF3.0, the first set of parton distribution functions (PDFs) determined with a methodology validated by a closure test. NNPDF3.0 uses a global dataset including HERA-II deep-inelastic inclusive cross-sections, the combined…

We review the present status of the determination of parton distribution functions (PDFs) in the light of the precision requirements for the LHC in Run 2 and other future hadron colliders. We provide brief reviews of all currently available…

High Energy Physics - Phenomenology · Physics 2016-09-21 A. Accardi , S. Alekhin , J. Blümlein , M. V. Garzelli , K. Lipka , W. Melnitchouk , S. Moch , R. Placakyte , J. F. Owens , E. Reya , N. Sato , A. Vogt , O. Zenaiev

We perform a global fit of parton distribution functions (PDFs) together with the strong coupling constant $\alpha_s$ and the quark masses $m_c$, $m_b$ and $m_t$ at next-to-leading order (NLO) in QCD. The analysis applies the…

High Energy Physics - Phenomenology · Physics 2018-09-10 S. Alekhin , J. Blümlein , S. Moch

I explain the current status of parton-distribution-function (PDF) studies and future experimental prospects on their determinations. First, unpolarized PDFs of the nucleon are introduced as a field of precision QCD physics including…

High Energy Physics - Phenomenology · Physics 2018-09-17 S. Kumano

We present the determination of a set of parton distributions of the nucleon, at next-to-leading order, from a global set of deep-inelastic scattering data: NNPDF1.0. The determination is based on a Monte Carlo approach, with neural…

High Energy Physics - Phenomenology · Physics 2010-05-12 Richard D. Ball , Luigi Del Debbio , Stefano Forte , Alberto Guffanti , Jose I. Latorre , Andrea Piccione , Juan Rojo , Maria Ubiali

In this talk, I overview the recent progress on the global analysis of nuclear parton distribution functions (nuclear PDFs). After first introducing the contemporary fits, the analysis procedures are quickly recalled and the ambiguities in…

High Energy Physics - Phenomenology · Physics 2018-03-14 Hannu Paukkunen

Uncertainties on parton distribution functions (PDFs) compromise discovery at the LHC for any new physics which can be described as a contact-interaction. PDF uncertainties also limit our ability to use W and Z cross-sections as an accurate…

High Energy Physics - Phenomenology · Physics 2007-07-12 A M Cooper-Sarkar

Heavy quark parton distribution functions (PDFs) play an important role in several Standard Model and New Physics processes. Most analyses rely on the assumption that the charm and bottom PDFs are generated perturbatively by gluon splitting…

High Energy Physics - Phenomenology · Physics 2016-08-08 Florian Lyonnet , Aleksander Kusina , Tomáš Ježo , Karol Kovařík , Fred Olness , Ingo Schienbein , Ji-Young Yu

We report current status of global analyses on nuclear parton distribution functions (NPDFs). The optimum NPDFs are determined by analyzing high-energy nuclear reaction data. Due to limited experimental measurements, antiquark modifications…

High Energy Physics - Phenomenology · Physics 2015-05-27 M. Hirai , S. Kumano , K. Saito

I outline some of the most recent developments on the global fit to parton distributions performed by the MRST collaboration.

High Energy Physics - Phenomenology · Physics 2015-06-25 R. S. Thorne , A. D. Martin , R. G. Roberts , W. J. Stirling