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The full exploitation of the increasingly precise LHC measurements is essential in order to reduce the uncertainty of theoretical predictions at hadron colliders. The NNPDF2.3 fit was the first PDF determination including the effect of the…

High Energy Physics - Phenomenology · Physics 2014-07-14 Maria Ubiali

We examine the equations to obtain atomic pair distribution functions (PDFs) from x-ray, neutron and electron powder diffraction data with a view to obtaining reliable and accurate PDFs from the raw data using a largely \emph{ad hoc}…

Materials Science · Physics 2012-11-20 Christopher L. Farrow , Simon J. L. Billinge

The need for accurate and precise polarised parton distribution functions (PDFs) is becoming increasingly crucial in view of the Electron-Ion Collider experimental program foreseen in the coming years. Two global PDF determinations at…

High Energy Physics - Phenomenology · Physics 2024-09-17 Amedeo Chiefa

In this proceeding we present the impact of the EW corrections on $t \bar t$ distributions focusing on the effect of the photon PDF. We use the {\sc NNPDF2.3QED} and {\sc CT14QED} PDF sets, which include the photon PDF. We discuss a…

High Energy Physics - Phenomenology · Physics 2016-12-23 Ioannis Tsinikos

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

The estimation and utilization of photometric redshift probability density functions (photo-$z$ PDFs) has become increasingly important over the last few years and currently there exist a wide variety of algorithms to compute photo-$z$'s,…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-05 M. Carrasco Kind , R. J. Brunner

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 present the nCTEQ15 global analysis of nuclear parton distribution functions (nPDFs). The main addition to the previous nCTEQ PDFs is the introduction of PDF uncertainties based on the Hessian method. Another important improvement is the…

High Energy Physics - Phenomenology · Physics 2016-11-04 A. Kusina

A precise knowledge of the quark and gluon structure of the proton, encoded by the parton distribution functions (PDFs), is of paramount importance for the interpretation of high-energy processes at present and future lepton-hadron and…

We present the first official release of the nCTEQ nuclear parton distribution functions with errors. The main addition to the previous nCTEQ PDFs is the introduction of PDF uncertainties based on the Hessian method. Another important…

High Energy Physics - Phenomenology · Physics 2016-08-17 A. Kusina , K. Kovarik , T. Jezo , D. B. Clark , C. Keppel , F. Lyonnet , J. G. Morfin , F. I. Olness , J. F. Owens , I. Schienbein , J. Y. Yu

Optimization constrained by high-fidelity computational models has potential for transformative impact. However, such optimization is frequently unattainable in practice due to the complexity and computational intensity of the model. An…

Numerical Analysis · Mathematics 2024-06-04 Joseph Hart , Bart van Bloemen Waanders

We present a review of the conceptual basis, present knowledge and recent progress in the field of global analysis of nuclear parton distribution functions (PDFs). After introducing the theoretical foundations and methodological approaches…

High Energy Physics - Phenomenology · Physics 2024-01-26 M. Klasen , H. Paukkunen

In this talk, we introduce our recently completed next-to-leading order (NLO) global analysis of the nuclear parton distribution functions (nPDFs) called EPS09 - a higher order successor to the well-known leading-order (LO) analysis EKS98…

High Energy Physics - Phenomenology · Physics 2014-11-18 H. Paukkunen , K. J. Eskola , C. A. Salgado

We discuss the Bayesian approach to the solution of inverse problems and apply the formalism to analyse the closure tests performed by the NNPDF collaboration. Starting from a comparison with the approach that is currently used for the…

High Energy Physics - Phenomenology · Physics 2022-05-04 Luigi Del Debbio , Tommaso Giani , Michael Wilson

Knowledge of parton distribution functions (PDFs) at large momentum fraction $ x $ is not only important to study the flavor and spin dynamics of quarks in the nucleon, but also to search for signals of new physics at collider experiments.…

High Energy Physics - Phenomenology · Physics 2020-04-22 Muhammad Goharipour , S. Rostami

A method to approximate continuous multi-dimensional probability density functions (PDFs) using their projections and correlations is described. The method is particularly useful for event classification when estimates of systematic…

Data Analysis, Statistics and Probability · Physics 2009-10-31 Dean Karlen

We discuss the recent CMS Collaboration measurement of $W^\pm$ boson production in p+Pb collisions at 8.16 TeV in terms of the constraining power on nuclear parton distribution functions (PDFs). The impact of the free-proton PDF…

High Energy Physics - Phenomenology · Physics 2022-04-13 Kari J. Eskola , Petja Paakkinen , Hannu Paukkunen , Carlos A. Salgado

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 current scientific standard in PDF uncertainty estimation relies either on repeated fits over artificially generated data to arrive at Monte Carlo samples of best fits or on the Hessian method, which uses a quadratic expansion of the…

High Energy Physics - Phenomenology · Physics 2024-07-23 Peter Risse , Nasim Derakhshanian , Tomas Ježo , Karol Kovařík , Aleksander Kusina

Random processes play a crucial role in scientific research, often characterized by distribution functions or probability density functions (PDFs). These PDFs serve as essential approximations of the actual and frequently undisclosed…

Methodology · Statistics 2023-06-06 Nico Schick