Precision NNLO determination of alpha_s(M_Z) using an unbiased global parton set

Richard D. Ball; Valerio Bertone; Luigi Del Debbio; Stefano Forte; Alberto Guffanti; Jose I. Latorre; Simone Lionetti; Juan Rojo; Maria Ubiali

doi:10.1016/j.physletb.2011.11.053

Precision NNLO determination of alpha_s(M_Z) using an unbiased global parton set

Richard D. Ball, Valerio Bertone, Luigi Del Debbio, Stefano Forte, Alberto Guffanti, Jose I. Latorre, Simone Lionetti, Juan Rojo, Maria Ubiali

(Astro)-Particles Physics

Research output: Contribution to Journal › Article › Academic › peer-review

65 Downloads (Pure)

Abstract

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.

Original language	English
Pages (from-to)	66-71
Journal	Physics Letters B
Volume	707
Issue number	1
DOIs	https://doi.org/10.1016/j.physletb.2011.11.053
Publication status	Published - 16 Jan 2012

Bibliographical note

11 pages, 6 figures. Various small corrections and improvements: Chi2 values for PDF fits provided, discussion of pulls clarified. Final version, to be published in Phys.Lett.B

Keywords

hep-ph

Access to Document

10.1016/j.physletb.2011.11.053

pdf

Handle.net

Persistent link

Cite this

@article{6538ec9e5ffc4279959699b8cff35ab6,

title = "Precision NNLO determination of alpha_s(M_Z) using an unbiased global parton set",

abstract = "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.",

keywords = "hep-ph",

author = "Ball, {Richard D.} and Valerio Bertone and Debbio, {Luigi Del} and Stefano Forte and Alberto Guffanti and Latorre, {Jose I.} and Simone Lionetti and Juan Rojo and Maria Ubiali",

note = "11 pages, 6 figures. Various small corrections and improvements: Chi2 values for PDF fits provided, discussion of pulls clarified. Final version, to be published in Phys.Lett.B",

year = "2012",

month = jan,

day = "16",

doi = "10.1016/j.physletb.2011.11.053",

language = "English",

volume = "707",

pages = "66--71",

journal = "Physics Letters B",

issn = "0370-2693",

publisher = "Elsevier",

number = "1",

}

TY - JOUR

T1 - Precision NNLO determination of alpha_s(M_Z) using an unbiased global parton set

AU - Ball, Richard D.

AU - Bertone, Valerio

AU - Debbio, Luigi Del

AU - Forte, Stefano

AU - Guffanti, Alberto

AU - Latorre, Jose I.

AU - Lionetti, Simone

AU - Rojo, Juan

AU - Ubiali, Maria

N1 - 11 pages, 6 figures. Various small corrections and improvements: Chi2 values for PDF fits provided, discussion of pulls clarified. Final version, to be published in Phys.Lett.B

PY - 2012/1/16

Y1 - 2012/1/16

N2 - 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.

AB - 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.

KW - hep-ph

U2 - 10.1016/j.physletb.2011.11.053

DO - 10.1016/j.physletb.2011.11.053

M3 - Article

SN - 0370-2693

VL - 707

SP - 66

EP - 71

JO - Physics Letters B

JF - Physics Letters B

IS - 1

ER -

Precision NNLO determination of alpha_s(M_Z) using an unbiased global parton set

Abstract

Bibliographical note

Keywords

Access to Document

Handle.net

Fingerprint

Cite this