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Related papers: Hide and seek: how PDFs can conceal New Physics

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We present a first attempt to design a quantum circuit for the determination of the parton content of the proton through the estimation of parton distribution functions (PDFs), in the context of high energy physics (HEP). The growing…

High Energy Physics - Phenomenology · Physics 2021-03-03 Adrián Pérez-Salinas , Juan Cruz-Martinez , Abdulla A. Alhajri , Stefano Carrazza

At large values of $x$ the parton distribution functions (PDFs) of the proton are poorly constrained and there are considerable variations between different global fits. Data at such high $x$ have already been published by the ZEUS…

High Energy Physics - Experiment · Physics 2021-07-14 Ritu Aggarwal

We consider the impact that can be made on our understanding of parton distributions (PDFs) and QCD from early measurements at the LHCb experiment. The high rapidity values make the experiment uniquely suited to a detailed study of small-x…

High Energy Physics - Phenomenology · Physics 2008-08-14 R. S. Thorne , A. D. Martin , W. J. Stirling , G. Watt

Data collected by the LHCb experiment allow proton structure functions to be probed in a kinematic region beyond the reach of other experiments, both at the LHC and further afield. In these proceedings the significant impact of LHCb Run 1…

High Energy Physics - Experiment · Physics 2019-08-13 Daniel Johnson

We present an updated global analysis of collinearly factorized nuclear parton distribution functions (PDFs) at next-to-leading order in perturbative QCD. In comparison to our previous fit, EPPS16, the present analysis includes more data…

High Energy Physics - Phenomenology · Physics 2022-05-25 Kari J. Eskola , Petja Paakkinen , Hannu Paukkunen , Carlos A. Salgado

Parton Distribution Functions (PDFs) contribute significantly to the uncertainty on the determination of the top-quark pole mass and other precision measurements at the Large Hadron Collider (LHC). It is crucial to understand these…

High Energy Physics - Phenomenology · Physics 2024-01-25 Jason P. Gombas , Reinhard Schwienhorst , Binbin Dong , Jarrett Fein

We present the new parton distribution functions (PDFs) from the CTEQ-TEA collaboration, obtained using a wide variety of high-precision Large Hadron Collider (LHC) data, in addition to the combined HERA I+II deep-inelastic scattering data…

The LHC data will provide sensitivity to an unification of the couplings at low energies in the range $\sim$10-100 TeV. It is demonstrated in this note that the lack of knowledge on the proton structure, specifically its gluon distribution,…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Ferrag

As is the case for all light coloured Standard Model particles, also photons and charged leptons appear as constituents in ultrarelativistic hadron beams, and admit a parton density function (PDF). It has been shown recently that the photon…

High Energy Physics - Phenomenology · Physics 2020-08-26 Luca Buonocore , Paolo Nason , Francesco Tramontano , Giulia Zanderighi

In global QCD fits of parton distribution functions (PDFs), a large part of the estimated uncertainty on the PDFs originates from the choices of parametric functional forms and fitting methodology. We argue that these types of uncertainties…

High Energy Physics - Phenomenology · Physics 2023-02-21 Aurore Courtoy , Joey Huston , Pavel Nadolsky , Keping Xie , Mengshi Yan , C. -P. Yuan

Representing the parton distribution functions (PDFs) of the proton and other hadrons through flexible, high-fidelity parametrizations has been a long-standing goal of particle physics phenomenology. This is particularly true since the…

High Energy Physics - Phenomenology · Physics 2024-06-21 Brandon Kriesten , T. J. Hobbs

The parton distribution functions (PDFs) are a non-negotiable input to almost all theory predictions at hadron colliders. In this talk, I introduce PDF determination by global analysis and discuss selected topics concerning recent relevant…

High Energy Physics - Phenomenology · Physics 2010-01-25 Graeme Watt

The LHC is foreseen to finally bring also the nuclear collisions to the TeV scale thereby providing new possibilities for physics studies, in particular related to the electro-weak sector of the Standard Model. We study here the Z and W…

High Energy Physics - Phenomenology · Physics 2015-03-17 Hannu Paukkunen , Carlos A. Salgado

The field of particle physics is at the crossroads. The discovery of a Higgs-like boson completed the Standard Model (SM), but the lacking observation of convincing resonances Beyond the SM (BSM) offers no guidance for the future of…

In this talk we present the results of the investigation on the so called double parton distribution functions (dPDFs), accessible quantities in high energy proton-proton and proton nucleus collisions, in double parton scattering processes…

High Energy Physics - Phenomenology · Physics 2021-02-03 Matteo Rinaldi

Experimental prospects for studying high-energy photon-photon and photon-proton interactions at the LHC are discussed. Assuming a typical LHC multipurpose detector, various signals and their irreducible backgrounds are presented after…

High Energy Physics - Phenomenology · Physics 2010-12-01 M. Vander Donckt

We compare predictions of nCTEQ15 nuclear parton distribution functions with proton-lead vector boson production data from the LHC. We select data sets that are most sensitive to nuclear PDFs and have potential to constrain them. We…

High Energy Physics - Phenomenology · Physics 2017-08-02 A. Kusina , F. Lyonnet , D. B. Clark , E. Godat , T. Jezo , K. Kovarik , F. I. Olness , I. Schienbein , J. Y. Yu

We present a methodology for the construction of parton distribution functions (PDFs) designed to provide an accurate representation of PDF uncertainties for specific processes or classes of processes with a minimal number of PDF error…

High Energy Physics - Phenomenology · Physics 2016-06-17 Stefano Carrazza , Stefano Forte , Zahari Kassabov , Juan Rojo

Hessian PDF reweighting, or "profiling", has become a widely used way to study the impact of a new data set on parton distribution functions (PDFs) with Hessian error sets. The available implementations of this method have resorted to a…

High Energy Physics - Phenomenology · Physics 2019-09-27 Kari J. Eskola , Petja Paakkinen , Hannu Paukkunen

In scenarios beyond the Standard Model (BSM) characterized by charged ($W^\prime$) or neutral ($Z^\prime$) massive gauge bosons with large width, resonant mass searches are not very effective, so that one has to exploit the tails of the…

High Energy Physics - Phenomenology · Physics 2022-02-25 Juri Fiaschi , Francesco Giuli , Francesco Hautmann , Stefano Moretti