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Precision NNLO determination of alpha_s(M_Z) using an unbiased global parton set
We determine the strong coupling alpha_s at NNLO in perturbative QCD using the global dataset input to the NNPDF2.1 NNLO parton fit: data from neutral and charged current deep-inelastic scattering, Drell-Yan, vector boson production and inclusive jets. We find alpha_s(M_Z)=0.1173+- 0.0007 (stat), wh...
Autores principales: | , , , , , , , , |
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Lenguaje: | eng |
Publicado: |
2011
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Materias: | |
Acceso en línea: | https://dx.doi.org/10.1016/j.physletb.2011.11.053 http://cds.cern.ch/record/1389920 |
_version_ | 1780923311296872448 |
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author | Ball, Richard D. Bertone, Valerio Del Debbio, Luigi Forte, Stefano Guffanti, Alberto Latorre, Jose I. Lionetti, Simone Rojo, Juan Ubiali, Maria |
author_facet | Ball, Richard D. Bertone, Valerio Del Debbio, Luigi Forte, Stefano Guffanti, Alberto Latorre, Jose I. Lionetti, Simone Rojo, Juan Ubiali, Maria |
author_sort | Ball, Richard D. |
collection | CERN |
description | We determine the strong coupling alpha_s at NNLO in perturbative QCD using the global dataset input to the NNPDF2.1 NNLO parton fit: data from neutral and charged current deep-inelastic scattering, Drell-Yan, vector boson production and inclusive jets. We find alpha_s(M_Z)=0.1173+- 0.0007 (stat), where the statistical uncertainty comes from the underlying data and uncertainties due to the analysis procedure are negligible. We show that the distribution of alpha_s values preferred by different experiments in the global fit is statistically consistent, without need for rescaling uncertainties by a "tolerance" factor. We show that if deep-inelastic data only are used, the best-fit value of alpha_s is somewhat lower, but consistent within one sigma with the global determination. We estimate the dominant theoretical uncertainty, from higher orders corrections, to be Delta alpha_s (pert) ~ 0.0009. |
id | cern-1389920 |
institution | Organización Europea para la Investigación Nuclear |
language | eng |
publishDate | 2011 |
record_format | invenio |
spelling | cern-13899202023-03-14T20:13:11Zdoi:10.1016/j.physletb.2011.11.053http://cds.cern.ch/record/1389920engBall, Richard D.Bertone, ValerioDel Debbio, LuigiForte, StefanoGuffanti, AlbertoLatorre, Jose I.Lionetti, SimoneRojo, JuanUbiali, MariaPrecision NNLO determination of alpha_s(M_Z) using an unbiased global parton setParticle Physics - PhenomenologyParticle Physics - PhenomenologyWe determine the strong coupling alpha_s at NNLO in perturbative QCD using the global dataset input to the NNPDF2.1 NNLO parton fit: data from neutral and charged current deep-inelastic scattering, Drell-Yan, vector boson production and inclusive jets. We find alpha_s(M_Z)=0.1173+- 0.0007 (stat), where the statistical uncertainty comes from the underlying data and uncertainties due to the analysis procedure are negligible. We show that the distribution of alpha_s values preferred by different experiments in the global fit is statistically consistent, without need for rescaling uncertainties by a "tolerance" factor. We show that if deep-inelastic data only are used, the best-fit value of alpha_s is somewhat lower, but consistent within one sigma with the global determination. We estimate the dominant theoretical uncertainty, from higher orders corrections, to be Delta alpha_s (pert) ~ 0.0009.We determine the strong coupling αs at NNLO in perturbative QCD using the global dataset input to the NNPDF2.1 NNLO parton fit: data from neutral and charged current deep-inelastic scattering, Drell–Yan, vector boson production and inclusive jets. We find αs(MZ)=0.1173±0.0007stat , where the statistical uncertainty comes from the underlying data and uncertainties due to the analysis procedure are negligible. We show that the distribution of αs values preferred by different experiments in the global fit is statistically consistent, without need for rescaling uncertainties by a “tolerance” factor. We show that if deep-inelastic data only are used, the best-fit value of αs is somewhat lower, but consistent within one sigma with the global determination. We find that the shift between the NLO and NNLO values of αs is Δαspert=0.0018 , and we estimate the uncertainty from higher-order corrections to be ΔαsNNLO∼0.0009 .We determine the strong coupling alpha_s at NNLO in perturbative QCD using the global dataset input to the NNPDF2.1 NNLO parton fit: data from neutral and charged current deep-inelastic scattering, Drell-Yan, vector boson production and inclusive jets. We find alpha_s(M_Z)=0.1173+- 0.0007 (stat), where the statistical uncertainty comes from the underlying data and uncertainties due to the analysis procedure are negligible. We show that the distribution of alpha_s values preferred by different experiments in the global fit is statistically consistent, without need for rescaling uncertainties by a "tolerance" factor. We show that if deep-inelastic data only are used, the best-fit value of alpha_s is somewhat lower, but consistent within one sigma with the global determination. We estimate the dominant theoretical uncertainty, from higher orders corrections, to be Delta alpha_s (pert) ~ 0.0009.arXiv:1110.2483CERN-PH-TH-2011-225EDINBURGH-2011-29FR-PHENO-2011-018TTK-11-50IFUM-985-FTCERN-PH-TH-2011-225EDINBURGH 2011-29FR-PHENO-2011-018IFUM-985-FTTTK-11-50oai:cds.cern.ch:13899202011-10-13 |
spellingShingle | Particle Physics - Phenomenology Particle Physics - Phenomenology Ball, Richard D. Bertone, Valerio Del Debbio, Luigi Forte, Stefano Guffanti, Alberto Latorre, Jose I. Lionetti, Simone Rojo, Juan Ubiali, Maria Precision NNLO determination of alpha_s(M_Z) using an unbiased global parton set |
title | Precision NNLO determination of alpha_s(M_Z) using an unbiased global parton set |
title_full | Precision NNLO determination of alpha_s(M_Z) using an unbiased global parton set |
title_fullStr | Precision NNLO determination of alpha_s(M_Z) using an unbiased global parton set |
title_full_unstemmed | Precision NNLO determination of alpha_s(M_Z) using an unbiased global parton set |
title_short | Precision NNLO determination of alpha_s(M_Z) using an unbiased global parton set |
title_sort | precision nnlo determination of alpha_s(m_z) using an unbiased global parton set |
topic | Particle Physics - Phenomenology Particle Physics - Phenomenology |
url | https://dx.doi.org/10.1016/j.physletb.2011.11.053 http://cds.cern.ch/record/1389920 |
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