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Related papers: The photon PDF within the CT18 global analysis

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We present progress towards the first unpolarized gluon quasi-PDF from lattice QCD using high-statistics measurement with $a \approx 0.12$ fm and two valence pion masses $M_\pi \approx 310$ and $690$ MeV generated on $2+1+1$-flavors of HISQ…

High Energy Physics - Lattice · Physics 2024-09-05 William Good , Kinza Hasan , Huey-Wen Lin

We propose an efficacious approach to derive the generalized parton distributions for the pion and proton, based upon prior knowledge of their respective parton distribution functions (PDFs). Our method leverages on integral representations…

High Energy Physics - Phenomenology · Physics 2024-06-17 Xiaobin Wang , Zanbin Xing , Minghui Ding , Khépani Raya , Lei Chang

Searches for new physics will increasingly depend on identifying deviations from precision Standard Model (SM) predictions. Quantum Chromodynamics (QCD) will necessarily play a central role in this endeavor as it provides the framework for…

High Energy Physics - Phenomenology · Physics 2016-04-20 Aleksander Kusina , Florian Lyonnet , Fredrick I. Olness , Ingo Schienbein

We present a new methodology that is able to yield a simultaneous determination of the Parton Distribution Functions (PDFs) of the proton alongside any set of parameters that determine the theory predictions; whether within the Standard…

High Energy Physics - Phenomenology · Physics 2022-05-12 Shayan Iranipour , Maria Ubiali

Parton distribution functions (PDFs) are nonperturbative objects defined by nonlocal light-cone correlations. They cannot be computed directly from Quantum Chromodynamics (QCD). Using a standard lattice QCD approach, it is possible to…

High Energy Physics - Phenomenology · Physics 2017-02-08 Alessandro Bacchetta , Marco Radici , Barbara Pasquini , Xiaonu Xiong

We study a few basic photon- and lepton-initiated processes at the LHC which can be computed using the recently developed photon and lepton parton densities. First, we consider the production of a massive scalar particle initiated by…

High Energy Physics - Phenomenology · Physics 2022-01-05 Luca Buonocore , Paolo Nason , Francesco Tramontano , Giulia Zanderighi

In this contribution, we review the results of the recent paper "The photon PDF from high-mass Drell Yan data at the LHC" (arXiv:1701.08553), where a determination of the photon PDF from fits to recent ATLAS measurements of high-mass…

High Energy Physics - Phenomenology · Physics 2017-08-15 Francesco Giuli

Beyond leading-order, perturbative QCD requires a choice of factorisation scheme to define the parton distribution functions (PDFs) and hard-process cross-section. The modified minimal-subtraction ($\overline{\mathrm{MS}}$) scheme has long…

High Energy Physics - Phenomenology · Physics 2025-05-12 Stéphane Delorme , Aleksander Kusina , Andrzej Siódmok , James Whitehead

Theoretical investigations into the deflection angle caused by microlenses offer a direct path to uncovering principles of the cosmological microlensing effect. This work specifically concentrates on the the probability density function…

Astrophysics of Galaxies · Physics 2023-08-30 Wenwen Zheng , Hou-Zun Chen , Xuechun Chen , Guoliang Li

Double parton distribution functions (dPDF), accessible in high energy proton-proton and proton nucleus collisions, encode information on how partons inside a proton are correlated among each other and could represent a tool to explore the…

High Energy Physics - Phenomenology · Physics 2015-09-30 Matteo Rinaldi , Sergio Scopetta , Marco Traini , Vicente Vento

A new ''$\mathtt{SK24}$'' non-singlet QCD analysis of the structure functions at the NNLO approximation is performed, utilizing the global fit of the data from various charged lepton scattering experiments. We extract the valence parton…

High Energy Physics - Phenomenology · Physics 2024-06-07 Javad Shahrzad , Ali Khorramian

By working in QED, we obtain the electron, positron, and photon Parton Distribution Functions (PDFs) of the unpolarised electron at the next-to-leading logarithmic accuracy. The PDFs account for all of the universal effects of initial-state…

High Energy Physics - Phenomenology · Physics 2022-07-26 V. Bertone , M. Cacciari , S. Frixione , G. Stagnitto

We study several sources of theoretical uncertainty in the determination of parton distributions (PDFs) which may affect current PDF sets used for precision physics at the Large Hadron Collider, and explain discrepancies between them. We…

High Energy Physics - Phenomenology · Physics 2013-05-09 The NNPDF Collaboration , Richard D. Ball , Valerio Bertone , Luigi Del Debbio , Stefano Forte , Alberto Guffanti , Juan Rojo , Maria Ubiali

A new analysis of the radiatively generated, LO quark (u,d,s,c,b) and gluon densities in the real, unpolarized photon, improved in respect to our paper [1], is presented. We perform four new global fits to the experimental data for…

High Energy Physics - Phenomenology · Physics 2011-01-25 F. Cornet , P. Jankowski , M. Krawczyk

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

Radiatively generated, LO quark (u,d,s,c,b) and gluon densities in the real, unpolarized photon, improved in respect to our previous paper, are presented. We perform three global fits to the F_2^gamma data, using the LO DGLAP evolution…

High Energy Physics - Phenomenology · Physics 2014-11-17 F. Cornet , P. Jankowski , M. Krawczyk

We present Fanto10, a new ensemble of NLO error parton distribution functions (PDFs) in a charged pion that provides the most detailed estimate of uncertainties from experimental, theoretical, and methodological sources in order to enable…

High Energy Physics - Phenomenology · Physics 2025-05-21 Lucas Kotz , Aurore Courtoy , Pavel Nadolsky , Maximiliano Ponce-Chavez

The statistical approach is used to calculate the parton distribution functions (PDFs) of the nucleon. At first it is assumed that the partons are free particles and the light-front kinematic variables are employed to extract the Bjorken…

High Energy Physics - Phenomenology · Physics 2014-03-27 A. Mirjalili , M. Dehghani , M. M. Yazdanpanah

We present a theoretical framework within which both the real and imaginary parts of the complex, two-photon exchange amplitude contributing to $K_L\rightarrow\mu^+\mu^-$ decay can be calculated using lattice QCD. The real part of this…

High Energy Physics - Phenomenology · Physics 2024-06-12 En-Hung Chao , Norman Christ

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
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