Measurement of Event Shapes in Proton-Antiproton Collisions at Center-of-Mass Energy 1.96 TeV

Abstract

A study of event shape observables in proton-antiproton collisions at 1.96 TeV is presented. The data for this analysis were recorded by the CDF II detector at the Tevatron collider. The variables studied are the transverse thrust and thrust minor, both defined in the plane perpendicular to the beam direction. The observables are measured using energies from unclustered calorimeter cells. In addition to studies of the differential distributions, we present the dependence of event shape mean values on the leading jet transverse energy. Data are compared with pythia Tune A and to resummed parton level predictions that were matched to fixed order results at NLO accuracy (NLO+NLL). Predictions from pythia Tune A agree fairly well with the data. However, the underlying event contributes significantly to these observables, making it difficult to make direct comparisons to the NLO+NLL predictions, which do not account for the underlying event. To overcome this difficulty, we introduce a new observable, a weighted difference of the mean values of the thrust and thrust minor, which is less sensitive to the underlying event, allowing for a comparison with NLO+NLL. Both pythia Tune A and the NLO+NLL calculations agree well within the 20% theoretical uncertainty with the data for this observable, indicating that perturbative QCD successfully describes shapes of the hadronic final states.

References in corpus (16)

• Global QCD Analysis of Parton Structure of the Nucleon: CTEQ5 Parton Distributions
• Measurement of the J/Psi Meson and b-Hadron Production Cross Sections in ppbar Collisions at sqrt s = 1960 GeV
• Renormalons
• Inclusive Jet Production, Parton Distributions, and the Search for New Physics
• Next-to-leading order calculation of three-jet observables in hadron-hadron collision
• Determination of the Jet Energy Scale at the Collider Detector at Fermilab
• Principles of general final-state resummation and automated implementation
• Phenomenology of event shapes at hadron colliders
• Event shapes in e+e- annihilation and deep inelastic scattering
• Resummed event shapes at hadron-hadron colliders
• The Underlying Event in Hard Interactions at the Tevatron pbarp Collider
• Generalized resummation of QCD final-state observables
• A Measurement of the QCD Colour Factors using Event Shape Distributions at sqrt(s)=14 GeV to 189 GeV
• Tests of Power Corrections for Event Shapes in e+e- Annihilation
• ${\alpha }_s$ 2002
• Determination of α_s from Event Shapes and Power Corrections

Cited by in corpus (15)

• Transverse sphericity of primary charged particles in minimum bias proton-proton collisions at $\sqrt{s}=0.9$, 2.76 and 7 TeV
• Determination of the strong coupling constant ${\alpha }_s$ from transverse energy-energy correlations in multijet events at $\sqrt{s}=8$ TeV using the ATLAS detector
• Soft evolution of multi-jet final states
• Measurement of transverse energy-energy correlations in multi-jet events in $pp$ collisions at $\sqrt{s}=7$ TeV using the ATLAS detector and determination of the strong coupling constant ${\alpha }_{\mathrm{s}}(m_Z)$
• Soft-drop grooming for hadronic event shapes
• Measurement of charged-particle event shape variables in sqrt(s) = 7 TeV proton-proton interactions with the ATLAS detector
• Transverse Energy-Energy Correlations in Next-to-Leading Order in ${\alpha }_s$ at the LHC
• Study of hadronic event-shape variables in multijet final states in pp collisions at sqrt(s) = 7 TeV
• Measurement of hadronic event shapes in high-$p_{\text{T}}$ multijet final states at $\sqrt{s}=13$ TeV with the ATLAS detector
• Next-to-next-to-leading logarithmic resummation for transverse thrust
• Event shape variables measured using multijet final states in proton-proton collisions at $\sqrt{s}=$ 13 TeV
• Event shapes for hadronic final state: experimental review
• Review of physics results from the Tevatron: QCD physics
• Factorization and resummation for transverse thrust
• Recent QCD results from the Tevatron