Resummation of heavy jet mass and comparison to LEP data

Abstract

The heavy jet mass distribution in e+e- collisions is computed to next-to-next-to-next-to leading logarithmic (NNNLL) and next-to-next-to leading fixed order accuracy (NNLO). The singular terms predicted from the resummed distribution are confirmed by the fixed order distributions allowing a precise extraction of the unknown soft function coefficients. A number of quantitative and qualitative comparisons of heavy jet mass and the related thrust distribution are made. From fitting to ALEPH data, a value of alpha_s is extracted, alpha_s(m_Z)=0.1220 +/- 0.0031, which is larger than, but not in conflict with, the corresponding value for thrust. A weighted average of the two produces alpha_s(m_Z) = 0.1193 +/- 0.0027, consistent with the world average. A study of the non-perturbative corrections shows that the flat direction observed for thrust between alpha_s and a simple non-perturbative shape parameter is not lifted in combining with heavy jet mass. The Monte Carlo treatment of hadronization gives qualitatively different results for thrust and heavy jet mass, and we conclude that it cannot be trusted to add power corrections to the event shape distributions at this accuracy. Whether a more sophisticated effective field theory approach to power corrections can reconcile the thrust and heavy jet mass distributions remains an open question.

33 pages, 14 figures. v2 added effect of lower numerical cutoff with improved extraction of the soft function constants; power correction discussion clarified. v3 small typos corrected

References in corpus (18)

• PYTHIA 6.4 Physics and Manual
• A precise determination of alpha_s from LEP thrust data using effective field theory
• Jets from Massive Unstable Particles: Top-Mass Determination
• NNLO corrections to event shapes in $e^{+}{e}^{-}$ annihilation
• Top Jets in the Peak Region: Factorization Analysis with NLL Resummation
• NNLO corrections to 3-jet observables in electron-positron annihilation
• Toward a NNLO calculation of the B-->X_s+gamma decay rate with a cut on photon energy: II. Two-loop result for the jet function
• Second-order QCD corrections to the thrust distribution
• Resummation and NLO Matching of Event Shapes with Effective Field Theory
• Designing Gapped Soft Functions for Jet Production
• Infrared structure of e+e- --> 3 jets at NNLO
• First determination of the strong coupling constant using NNLO predictions for hadronic event shapes in e^+e^- annihilations
• Determination of the strong coupling constant using matched NNLO+NLLA predictions for hadronic event shapes in e+e- annihilations
• Event Generation from Effective Field Theory
• Constraining Light Colored Particles with Event Shapes
• Improving jet distributions with effective field theory
• Hemisphere Soft Function at O(alpha_s^2) for Dijet Production in e+e- Annihilation
• Global Fit of alpha_s(m_Z) to Thrust at NNNLL Order with Power Corrections

Cited by in corpus (23)

• Thrust at N^3LL with Power Corrections and a Precision Global Fit for alphas(mZ)
• Power Counting to Better Jet Observables
• C-parameter Distribution at N${}^3$LL${}^{\prime }$ including Power Corrections
• Webs in multiparton scattering using the replica trick
• A Precise Determination of ${\alpha }_s$ from the C-parameter Distribution
• Top Quark Mass Calibration for Monte Carlo Event Generators
• Energy-energy correlation in electron-positron annihilation at NNLL+NNLO accuracy
• Analytic Next-To-Leading Order Calculation of Energy-Energy Correlation in Gluon-Initiated Higgs Decays
• Non-global Logarithms at 3 Loops, 4 Loops, 5 Loops and Beyond
• NLO QCD corrections to five-jet production at LEP and the extraction of alpha_s(M_Z)
• Jet Shape Resummation Using Soft-Collinear Effective Theory
• $C$-parameter hadronisation in the symmetric 3-jet limit and impact on ${\alpha }_s$ fits
• Factorization for the light-jet mass and hemisphere soft function
• Precision physics with inclusive QCD processes
• NNLO QCD corrections to event orientation in e+e- annihilation
• Threshold Hadronic Event Shapes with Effective Field Theory
• Analytic Calculation of 1-Jettiness in DIS at $\mathcal{O}({\alpha }_s)$
• Resummation of Jet Shapes and Extracting Properties of the Quark-Gluon Plasma
• Investigating the Quantum Properties of Jets and the Search for a Supersymmetric Top Quark Partner with the ATLAS Detector
• Removing phase-space restrictions in factorized cross sections
• The Evolution of Soft Collinear Effective Theory
• QCD Beyond Leading Power
• Thrust distribution resummation in e^{+}e^{-} collisions