A5034411286- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Quantum Chromodynamics and Particle Interactions
- Distributed and Parallel Computing Systems
- Superconducting Materials and Applications
- Computational Physics and Python Applications
- Metal and Thin Film Mechanics
- Particle Accelerators and Free-Electron Lasers
- Vacuum and Plasma Arcs
- Radioactivity and Radon Measurements
- Nuclear Physics and Applications
- Advanced Data Storage Technologies
- Particle Detector Development and Performance
- Radiation Detection and Scintillator Technologies
- Advanced Semiconductor Detectors and Materials
- Radioactive Decay and Measurement Techniques
- Semiconductor Quantum Structures and Devices
- International Science and Diplomacy
- Scientific Computing and Data Management
- Radiomics and Machine Learning in Medical Imaging
- Neutrino Physics Research
- Particle accelerators and beam dynamics
- Scientific Measurement and Uncertainty Evaluation
- Advanced materials and composites
- Veterinary medicine and infectious diseases
Durham University
2003-2020
King's Inns
2020
University of Zurich
2013-2014
Australian Nuclear Science and Technology Organisation
1993-2013
European Organization for Nuclear Research
2008-2012
University College London
2006-2009
Deutsches Elektronen-Synchrotron DESY
2005-2007
Universität Hamburg
2007
The Fortran LHAPDF library has been a long-term workhorse in particle physics, providing standardised access to parton density functions for experimental and phenomenological purposes alike, following on from the venerable PDFLIB package. During Run 1 of LHC, however, several fundamental limitations LHAPDF’s design have became deeply problematic, restricting usability important physics-study procedures dangerous avenues by which silently obtain incorrect results. In this paper we present 6...
We present a simultaneous analysis, within an impact parameter dependent saturated dipole model, of exclusive diffractive vector meson ($J/\ensuremath{\psi}$, $\ensuremath{\phi}$, and $\ensuremath{\rho}$) production, deeply virtual Compton scattering the total ${\ensuremath{\gamma}}^{*}p$ cross section data measured at HERA. Various sections as function kinematic variables ${Q}^{2}$, $W$ $t$ are well described, with little sensitivity to details wave functions. determine properties gluon...
This document is intended as a study of benchmark cross sections at the LHC (at 7 TeV) NLO using modern parton distribution functions currently available from 6 PDF fitting groups that have participated in this exercise. It also contains succinct user guide to computation PDFs, uncertainties and correlations sets. A companion note, submitted archive, provides an interim summary current recommendations PDF4LHC working group for use LHC, section uncertainty calculations.
HERAFitter is an open-source package that provides a framework for the determination of parton distribution functions (PDFs) proton and many different kinds analyses in Quantum Chromodynamics (QCD). It encodes results from wide range experimental measurements lepton–proton deep inelastic scattering proton–proton (proton–antiproton) collisions at hadron colliders. These are complemented with variety theoretical options calculating PDF-dependent cross section predictions corresponding to...
We show that the color glass condensate dipole model of Iancu, Itakura, and Munier, improved to include impact parameter dependence, gives a good fit total ${\ensuremath{\gamma}}^{*}p$ cross section measured at HERA if anomalous dimension saturation scale, ${\ensuremath{\gamma}}_{s}$, is treated as free parameter. find optimum value ${\ensuremath{\gamma}}_{s}=0.46$ close determined from numerical solution Balitsky-Kovchegov equation. The dependent scale generally less than $0.5\text{ }\text{...
The Durham High Energy Physics Database (HEPData) has been built up over the past four decades as a unique open-access repository for scattering data from experimental particle physics papers. It comprises points underlying several thousand publications. Over last two years, HEPData software completely rewritten using modern computing technologies an overlay on Invenio v3 digital library framework. is open source with new site available at https://hepdata.net now replacing previous...
We review the current state of art in determination parton substructure nucleon, as expressed terms distribution functions (PDFs), and probed high-energy lepton-hadron hadron-hadron collisions, we assess their implications for precision collider phenomenology, particular at Large Hadron Collider (LHC). theoretical foundations PDF determination: way cross sections are PDFs using perturbative QCD factorization evolution, methodology used to extract from experimental data, which different...
This report summarizes the activities of SM and NLO Multileg Working Group Workshop "Physics at TeV Colliders", Les Houches, France 8-26 June, 2009.
The current PDF4LHC recommendation to estimate uncertainties due parton distribution functions (PDFs) in theoretical predictions for LHC processes involves the combination of separate computed using PDF sets from different groups, each which comprises a relatively large number either Hessian eigenvectors or Monte Carlo (MC) replicas. While many fixed-order and shower programs allow evaluation single set at no additional CPU cost, this feature is not universal, and, moreover, posteriori least...
A bstract We investigate the Monte Carlo approach to propagation of experimental uncertainties within context established “MSTW 2008” global analysis parton distribution functions (PDFs) proton at next-to-leading order in strong coupling. show that using replicas original data gives PDF good agreement with usual Hessian standard Δ χ 2 = 1 criterion, then we explore potential parameterisation bias by increasing number free parameters, concluding any is likely be small, exception valence-quark...
We describe the use of doubly unintegrated parton distributions in hadron-hadron collisions, using ${(z,k}_{t})$-factorization prescription where transverse momentum incoming is generated last evolution step. apply this formalism to calculate ${(P}_{T})$ produced W and Z bosons compare predictions Tevatron run 1 data. find that observed ${P}_{T}$ can be almost entirely by leading order ${q}_{1}{q}_{2}\ensuremath{\rightarrow}W,Z$ subprocesses, known universal quark distributions. also...
We compare predictions for the W, Z, gg → H and $ t\bar{t} total cross sections at Large Hadron Collider (LHC), a centre-of-mass energy of 7 TeV, using most recent publicly available next-to-leading order next-to-next-to-leading parton distribution functions (PDFs) from all PDF fitting groups. In particular, we focus on dependence different values strong coupling, α S (M Z 2), used by each group. also perform comparison relevant quark-antiquark gluon-gluon luminosity functions. make some...
HERAFitter is an open-source package that provides a framework for the determination of parton distribution functions (PDFs) proton and many different kinds analyses in Quantum Chromodynamics (QCD). It encodes results from wide range experimental measurements lepton-proton deep inelastic scattering proton-proton (proton-antiproton) collisions at hadron colliders. These are complemented with variety theoretical options calculating PDF-dependent cross section predictions corresponding to...
We provide predictions for the rapidity distributions of exclusive photoproduced $J/\ensuremath{\psi}$ and $\ensuremath{\Upsilon}$ mesons, ${Z}^{0}$ bosons, at Tevatron Large Hadron Collider. use equivalent-photon approximation with photon-proton cross sections given by impact parameter dependent dipole saturation model, which has already been shown to give a good description wide variety HERA data. derive quark-antiquark light-cone wave functions timelike neutral electroweak bosons. An...
We respond to some criticism questioning the validity of current Standard Model Higgs exclusion limits at Tevatron, due significant dependence dominant production cross section from gluon-gluon fusion on choice parton distribution functions (PDFs) and strong coupling (alpha_S). demonstrate ability Tevatron jet data discriminate between different high-x gluon distributions, performing a detailed quantitative comparison show that fits not explicitly including these fail give good description....
We motivate a measurement of various ratios W and Z cross sections at the Large Hadron Collider (LHC) large values boson transverse momentum (p T ≳ M W,Z ). study dependence predictions for these cross-section on multiplicity associated jets, p LHC centre-of-mass energy. present flavour decomposition initial-state partons an evaluation theoretical uncertainties. show that + /W − ratio is sensitive to up-quark down-quark parton distribution functions (PDFs), while other uncertainties are...