1
|
Britzger D, Gehrmann-De Ridder A, Gehrmann T, Glover EWN, Gwenlan C, Huss A, Pires J, Rabbertz K, Savoiu D, Sutton MR, Stark J. NNLO interpolation grids for jet production at the LHC. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2022; 82:930. [PMID: 36277417 PMCID: PMC9581847 DOI: 10.1140/epjc/s10052-022-10880-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 10/06/2022] [Indexed: 06/16/2023]
Abstract
Fast interpolation-grid frameworks facilitate an efficient and flexible evaluation of higher-order predictions for any choice of parton distribution functions or value of the strong coupling α s . They constitute an essential tool for the extraction of parton distribution functions and Standard Model parameters, as well as studies of the dependence of cross sections on the renormalisation and factorisation scales. The APPLfast project provides a generic interface between the parton-level Monte Carlo generator and both the APPLgrid and the fastNLO libraries for the grid interpolation. The extension of the project to include hadron-hadron collider processes at next-to-next-to-leading order in perturbative QCD is presented, together with an application for jet production at the LHC.
Collapse
Affiliation(s)
- D. Britzger
- Max-Planck-Institut für Physik, Föhringer Ring 6, 80805 Munich, Germany
| | - A. Gehrmann-De Ridder
- Institute for Theoretical Physics, ETH, Wolfgang-Pauli-Strasse 27, 8093 Zurich, Switzerland
- Physik-Institut, Universität Zürich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - T. Gehrmann
- Physik-Institut, Universität Zürich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - E. W. N. Glover
- Institute for Particle Physics Phenomenology, Durham University, Durham, DH1 3LE UK
| | - C. Gwenlan
- Department of Physics, The University of Oxford, Oxford, OX1 3RH UK
| | - A. Huss
- Theoretical Physics Department, CERN, 1211 Geneva 23, Switzerland
| | - J. Pires
- LIP, Avenida Professor Gama Pinto 2, 1649-003 Lisbon, Portugal
- Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisbon, Portugal
| | - K. Rabbertz
- Institut für Experimentelle Teilchenphysik (ETP), KIT, Wolfgang-Gaede-Str. 1, 76131 Karlsruhe, Germany
- Experimental Physics Department, CERN, 1211 Geneva 23, Switzerland
| | - D. Savoiu
- Institut für Experimentalphysik, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - M. R. Sutton
- Department of Physics and Astronomy, The University of Sussex, Brighton, BN1 9RH UK
| | - J. Stark
- Institut für Experimentelle Teilchenphysik (ETP), KIT, Wolfgang-Gaede-Str. 1, 76131 Karlsruhe, Germany
| |
Collapse
|
2
|
Czakon M, Mitov A, Poncelet R. Next-to-Next-to-Leading Order Study of Three-Jet Production at the LHC. PHYSICAL REVIEW LETTERS 2021; 127:152001. [PMID: 34678021 DOI: 10.1103/physrevlett.127.152001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 08/27/2021] [Accepted: 09/10/2021] [Indexed: 06/13/2023]
Abstract
Multijet rates at hadron colliders provide a unique possibility for probing quantum chromodynamics (QCD), the theory of strong interactions. By comparing theory predictions with collider data, one can directly test perturbative QCD, extract fundamental parameters like the strong coupling α_{s}, and search for physics beyond the standard model. In this work we calculate, for the first time, the next-to-next-to-leading order (NNLO) QCD corrections to typical three-jet observables and to differential three-to-two jet ratios. The calculation is complete apart from the three-jet double virtual contributions which are included in the leading-color approximation. We demonstrate that the inclusion of the NNLO corrections significantly reduces the dependence of those observables on the factorization and renormalization scales. Besides its phenomenological value, this proof-of-principle computation represents a milestone in perturbative QCD.
Collapse
Affiliation(s)
- Michał Czakon
- Institut für Theoretische Teilchenphysik und Kosmologie, RWTH Aachen University, D-52056 Aachen, Germany
| | - Alexander Mitov
- Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Rene Poncelet
- Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom
| |
Collapse
|
3
|
Bellm J, Buckley A, Chen X, Ridder AGD, Gehrmann T, Glover N, Höche S, Huss A, Huston J, Kuttimalai S, Pires J, Plätzer S, Re E. Jet cross sections at the LHC and the quest for higher precision. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2020; 80:93. [PMID: 32089641 PMCID: PMC7002464 DOI: 10.1140/epjc/s10052-019-7574-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Accepted: 12/20/2019] [Indexed: 06/10/2023]
Abstract
We perform a phenomenological study of Z plus jet, Higgs plus jet and di-jet production at the Large Hadron Collider. We investigate in particular the dependence of the leading jet cross section on the jet radius as a function of the jet transverse momentum. Theoretical predictions are obtained using perturbative QCD calculations at the next-to and next-to-next-to-leading order, using a range of renormalization and factorization scales. The fixed order predictions are compared to results obtained from matching next-to-leading order calculations to parton showers. A study of the scale dependence as a function of the jet radius is used to provide a better estimate of the scale uncertainty for small jet sizes. The non-perturbative corrections as a function of jet radius are estimated from different generators.
Collapse
Affiliation(s)
- Johannes Bellm
- Department of Astronomy and Theoretical Physics, Lund University, 223 62 Lund, Sweden
| | - Andy Buckley
- School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ UK
| | - Xuan Chen
- Institut für Theoretische Physik, Universität Zürich, 8057 Zürich, Switzerland
| | - Aude Gehrmann-De Ridder
- Institut für Theoretische Physik, Universität Zürich, 8057 Zürich, Switzerland
- Institute for Theoretical Physics, ETH, 8093 Zürich, Switzerland
| | - Thomas Gehrmann
- Institut für Theoretische Physik, Universität Zürich, 8057 Zürich, Switzerland
| | - Nigel Glover
- Institute for Particle Physics Phenomenology, Durham University, Durham, DH1 3LE UK
| | - Stefan Höche
- SLAC National Accelerator Laboratory, Menlo Park, CA 94025 USA
- Fermi National Accelerator Laboratory, Batavia, IL 60510-0500 USA
| | - Alexander Huss
- Theoretical Physics Department, CERN, 1211 Geneva 23, Switzerland
| | - Joey Huston
- Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 USA
| | | | - Joao Pires
- CFTP, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
| | - Simon Plätzer
- Fakultät Physik, University of Vienna, 1010 Vienna, Austria
| | - Emanuele Re
- Theoretical Physics Department, CERN, 1211 Geneva 23, Switzerland
- Laboratoire d’Annecy-le-Vieux de Physique Théorique, Université Grenoble Alpes, Université Savoie Mont Blanc, CNRS, 74940 Annecy, France
| |
Collapse
|
4
|
Ridder AGD, Gehrmann T, Glover EWN, Huss A, Pires J. Triple Differential Dijet Cross Section at the LHC. PHYSICAL REVIEW LETTERS 2019; 123:102001. [PMID: 31573318 DOI: 10.1103/physrevlett.123.102001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Indexed: 06/10/2023]
Abstract
The measurement of the triple-differential dijet production cross section as a function of the average transverse momentum p_{T,avg}, half the rapidity separation y^{*}, and the boost y_{b} of the two leading jets in the event enables a kinematical scan of the underlying parton momentum distributions. We compute for the first time the second-order perturbative QCD corrections to this triple-differential dijet cross section, at leading color in all partonic channels, thereby enabling precision studies with LHC dijet data. A detailed comparison with experimental CMS 8 TeV data is performed, demonstrating how the shape of this differential cross section probes the parton densities in different kinematical ranges.
Collapse
Affiliation(s)
- A Gehrmann-De Ridder
- Institute for Theoretical Physics, ETH, CH-8093 Zürich, Switzerland
- Department of Physics, Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | - T Gehrmann
- Department of Physics, Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | - E W N Glover
- Institute for Particle Physics Phenomenology, University of Durham, Durham DH1 3LE, United Kingdom
| | - A Huss
- Theoretical Physics Department, CERN, 1211 Geneva 23, Switzerland
| | - J Pires
- CFTP, Instituto Superior Técnico, Universidade de Lisboa, P-1049-001 Lisboa, Portugal
- LIP, Avenida Professor Gama Pinto 2, P-1649-003 Lisboa, Portugal
| |
Collapse
|
5
|
Badger S, Chicherin D, Gehrmann T, Heinrich G, Henn JM, Peraro T, Wasser P, Zhang Y, Zoia S. Analytic Form of the Full Two-Loop Five-Gluon All-Plus Helicity Amplitude. PHYSICAL REVIEW LETTERS 2019; 123:071601. [PMID: 31491100 DOI: 10.1103/physrevlett.123.071601] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Indexed: 06/10/2023]
Abstract
We compute the full-color two-loop five-gluon amplitude for the all-plus helicity configuration. In order to achieve this, we calculate the required master integrals for all permutations of the external legs, in the physical scattering region. We verify the expected divergence structure of the amplitude and extract the finite hard function. We further validate our result by checking the factorization properties in the collinear limit. Our result is fully analytic and valid in the physical scattering region. We express it in a compact form containing logarithms, dilogarithms, and rational functions.
Collapse
Affiliation(s)
- S Badger
- Institute for Particle Physics Phenomenology, Durham University, Durham DH1 3LE, United Kingdom
| | - D Chicherin
- Max-Planck-Institut für Physik, Werner-Heisenberg-Institut, D-80805 München, Germany
| | - T Gehrmann
- Physik-Institut, Universität Zürich, Wintherturerstrasse 190, CH-8057 Zürich, Switzerland
| | - G Heinrich
- Max-Planck-Institut für Physik, Werner-Heisenberg-Institut, D-80805 München, Germany
| | - J M Henn
- Max-Planck-Institut für Physik, Werner-Heisenberg-Institut, D-80805 München, Germany
| | - T Peraro
- Physik-Institut, Universität Zürich, Wintherturerstrasse 190, CH-8057 Zürich, Switzerland
| | - P Wasser
- PRISMA+Cluster of Excellence, Johannes Gutenberg University, D-55099 Mainz, Germany
| | - Y Zhang
- Max-Planck-Institut für Physik, Werner-Heisenberg-Institut, D-80805 München, Germany
- Interdisciplinary Center for Theoretical Study, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - S Zoia
- Max-Planck-Institut für Physik, Werner-Heisenberg-Institut, D-80805 München, Germany
| |
Collapse
|
6
|
|
7
|
Khalek RA, Bailey S, Gao J, Harland-Lang L, Rojo J. Towards ultimate parton distributions at the high-luminosity LHC. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2018; 78:962. [PMID: 30881213 PMCID: PMC6394281 DOI: 10.1140/epjc/s10052-018-6448-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 11/11/2018] [Indexed: 06/09/2023]
Abstract
Since its start of data taking, the LHC has provided an impressive wealth of information on the quark and gluon structure of the proton. Indeed, modern global analyses of parton distribution functions (PDFs) include a wide range of LHC measurements of processes such as the production of jets, electroweak gauge bosons, and top quark pairs. In this work, we assess the ultimate constraining power of LHC data on the PDFs that can be expected from the complete dataset, in particular after the High-Luminosity (HL) phase, starting in around 2025. The huge statistics of the HL-LHC, delivering L = 3 ab - 1 to ATLAS and CMS and L = 0.3 ab - 1 to LHCb, will lead to an extension of the kinematic coverage of PDF-sensitive measurements as well as to an improvement in their statistical and systematic uncertainties. Here we generate HL-LHC pseudo-data for different projections of the experimental uncertainties, and then quantify the resulting constraints on the PDF4LHC15 set by means of the Hessian profiling method. We find that HL-LHC measurements can reduce PDF uncertainties by up to a factor of 2 to 4 in comparison to state-of-the-art fits, leading to few-percent uncertainties for important observables such as the Higgs boson transverse momentum distribution via gluon-fusion. Our results illustrate the significant improvement in the precision of PDF fits achievable from hadron collider data alone, and motivate the continuation of the ongoing successful program of PDF-sensitive measurements by the LHC collaborations.
Collapse
Affiliation(s)
- Rabah Abdul Khalek
- Department of Physics and Astronomy, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands
- Nikhef Theory Group, Science Park 105, 1098 XG Amsterdam, The Netherlands
| | - Shaun Bailey
- Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford, OX1 3PU UK
| | - Jun Gao
- Institute of Nuclear and Particle Physics, Shanghai Key Laboratory for Particle Physics and Cosmology, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, China
| | - Lucian Harland-Lang
- Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford, OX1 3PU UK
| | - Juan Rojo
- Department of Physics and Astronomy, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands
- Nikhef Theory Group, Science Park 105, 1098 XG Amsterdam, The Netherlands
| |
Collapse
|