Search for Quark Contact Interactions in Dijet Angular Distributions in pp Collisions at sqrt(s) = 7 TeV Measured with the ATLAS Detector

AGH University of Science and Technology in Kraków, Cracovia, Lesser Poland Voivodeship, Poland
Physics Letters B (Impact Factor: 6.13). 09/2010; 694(4-5). DOI: 10.1016/j.physletb.2010.10.021
Source: OAI


Dijet angular distributions from the first LHC pp collisions at center-of-mass energy sqrt(s) = 7 TeV have been measured with the ATLAS detector. The dataset used for this analysis represents an integrated luminosity of 3.1 pb-1. Dijet $\chi$ distributions and centrality ratios have been measured up to dijet masses of 2.8 TeV, and found to be in good agreement with Standard Model predictions. Analysis of the $\chi$ distributions excludes quark contact interactions with a compositeness scale $\Lambda$ below 3.4 TeV, at 95% confidence level, significantly exceeding previous limits.

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Available from: Tonguc Rador, Jul 21, 2014
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    • "chosen mass intervals 800 < m jj < 1200 GeV and m jj > 1200 GeV. Only the first four ATLAS bins with 1 < χ < 3.32 are included in this analysis, which we base on the optimized sensitivity to quark contact interactions given in Ref. [30]. As an example of this search in action, the constraints from dijet contact interaction searches are shown as the solid dark yellow line of Fig. 2, which refers to the effective field theory of section 2. "
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