Application of the principle of maximum conformality to the hadroproduction of the Higgs boson at the LHC
Abstract
We present improved perturbative QCD (pQCD) predictions for Higgs boson hadroproduction at the LHC by applying the principle of maximum conformality (PMC), a procedure which resums the pQCD series using the renormalization group (RG), thereby eliminating the dependence of the predictions on the choice of the renormalization scheme while minimizing sensitivity to the initial choice of the renormalization scale. In previous pQCD predictions for Higgs boson hadroproduction, it has been conventional to assume that the renormalization scale μ r of the QCD coupling α s ( μ r ) is the Higgs mass and then to vary this choice over the range 1 / 2 m H < μ r < 2 m H in order to estimate the theory uncertainty. However, this error estimate is only sensitive to the nonconformal β terms in the pQCD series, and thus it fails to correctly estimate the theory uncertainty in cases where a pQCD series has large higherorder contributions, as is the case for Higgs boson hadroproduction. Furthermore, this ad hoc choice of scale and range gives pQCD predictions which depend on the renormalization scheme being used, in contradiction to basic RG principles. In contrast, after applying the PMC, we obtain nexttonexttoleadingordermore »
 Authors:
 Publication Date:
 Research Org.:
 SLAC National Accelerator Lab., Menlo Park, CA (United States)
 Sponsoring Org.:
 USDOE Office of Science (SC), High Energy Physics (HEP) (SC25)
 OSTI Identifier:
 1253091
 Report Number(s):
 SLACPUB16521
Journal ID: ISSN 24700010; PRVDAQ; arXiv:1605.02572
 DOE Contract Number:
 AC0276SF00515
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review D; Journal Volume: 94; Journal Issue: 5
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ExperimentHEP; PhenomenologyHEP; HEPEX; HEPTH
Citation Formats
Wang, ShengQuan, Wu, XingGang, Brodsky, Stanley J., and Mojaza, Matin. Application of the principle of maximum conformality to the hadroproduction of the Higgs boson at the LHC. United States: N. p., 2016.
Web. doi:10.1103/PhysRevD.94.053003.
Wang, ShengQuan, Wu, XingGang, Brodsky, Stanley J., & Mojaza, Matin. Application of the principle of maximum conformality to the hadroproduction of the Higgs boson at the LHC. United States. doi:10.1103/PhysRevD.94.053003.
Wang, ShengQuan, Wu, XingGang, Brodsky, Stanley J., and Mojaza, Matin. 2016.
"Application of the principle of maximum conformality to the hadroproduction of the Higgs boson at the LHC". United States.
doi:10.1103/PhysRevD.94.053003. https://www.osti.gov/servlets/purl/1253091.
@article{osti_1253091,
title = {Application of the principle of maximum conformality to the hadroproduction of the Higgs boson at the LHC},
author = {Wang, ShengQuan and Wu, XingGang and Brodsky, Stanley J. and Mojaza, Matin},
abstractNote = {We present improved perturbative QCD (pQCD) predictions for Higgs boson hadroproduction at the LHC by applying the principle of maximum conformality (PMC), a procedure which resums the pQCD series using the renormalization group (RG), thereby eliminating the dependence of the predictions on the choice of the renormalization scheme while minimizing sensitivity to the initial choice of the renormalization scale. In previous pQCD predictions for Higgs boson hadroproduction, it has been conventional to assume that the renormalization scale μ r of the QCD coupling α s ( μ r ) is the Higgs mass and then to vary this choice over the range 1 / 2 m H < μ r < 2 m H in order to estimate the theory uncertainty. However, this error estimate is only sensitive to the nonconformal β terms in the pQCD series, and thus it fails to correctly estimate the theory uncertainty in cases where a pQCD series has large higherorder contributions, as is the case for Higgs boson hadroproduction. Furthermore, this ad hoc choice of scale and range gives pQCD predictions which depend on the renormalization scheme being used, in contradiction to basic RG principles. In contrast, after applying the PMC, we obtain nexttonexttoleadingorder RG resummed pQCD predictions for Higgs boson hadroproduction which are renormalizationscheme independent and have minimal sensitivity to the choice of the initial renormalization scale. Taking m H = 125 GeV , the PMC predictions for the p p → H X Higgs inclusive hadroproduction cross sections for various LHC centerofmass energies are σ Incl  7 TeV = 21.2 1 + 1.36  1.32 pb , σ Incl  8 TeV = 27.3 7 + 1.65  1.59 pb , and σ Incl  13 TeV = 65.7 2 + 3.46  3.0 pb . We also predict the fiducial cross section σ fid ( p p → H → γ γ ) : σ fid  7 TeV = 30.1 + 2.3  2.2 fb , σ fid  8 TeV = 38.3 + 2.9  2.8 fb , and σ fid  13 TeV = 85.8 + 5.7  5.3 fb . The error limits in these predictions include the small residual highorder renormalizationscale dependence plus the uncertainty from the factorization scale. The PMC predictions show better agreement with the ATLAS measurements than the LHC Higgs Cross Section Working Group predictions which are based on conventional renormalizationscale setting.},
doi = {10.1103/PhysRevD.94.053003},
journal = {Physical Review D},
number = 5,
volume = 94,
place = {United States},
year = 2016,
month = 9
}

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