First Measurement of Hadronic Event Shapes in pp Collisions at sqrt(s)=7 TeV

Abstract

Hadronic event shapes have been measured in proton-proton collisions at sqrt(s)=7 TeV, with a data sample collected with the CMS detector at the LHC. The sample corresponds to an integrated luminosity of 3.2 inverse picobarns. Event-shape distributions, corrected for detector response, are compared with five models of QCD multijet production.

Figures (3)

• Figure 1: Distributions of the logarithm of the central transverse thrust (top left) and central thrust minor (top right) for events with a leading jet $p_{\mathrm{T}}$ between 90 and 125${\,\text{Ge\spaceV\space/\space}c}$, from data and from five MC simulations. The error bars on the data points represent the statistical uncertainty on the data, and the shaded (blue) bands represent the sum of statistical and systematic errors. The lower plots show the ratio between data and the different simulated samples.
• Figure 2: Distributions of the logarithm of the central transverse thrust (top left) and central thrust minor (top right) for events with a leading jet $p_{\mathrm{T}}$ between 125 and 200${\,\text{Ge\spaceV\space/\space}c}$, from data and from five MC simulations. The error bars on the data points represent the statistical uncertainty on the data, and the shaded (blue) bands represent the sum of statistical and systematic errors. The lower plots show the ratio between data and the different simulated samples.
• Figure 3: Distributions of the logarithm of the central transverse thrust (top left) and central thrust minor (top right) for events with a leading jet $p_{\mathrm{T}}\xspace{}_{,1} > 200{\,\text{Ge\spaceV\space/\space}c}\xspace$, from data and from five MC simulations. The error bars on the data points represent the statistical uncertainty on the data, and the shaded (blue) bands represent the sum of statistical and systematic errors. The lower plots show the ratio between data and the different simulated samples.