Home > Research > Publications & Outputs > Measurement of spin correlation in top-antitop ...

Electronic data

  • PhysRevLett.114.142001

    Rights statement: © 2015 CERN, for the ATLAS Collaboration

    Final published version, 476 KB, PDF document

Links

Text available via DOI:

View graph of relations

Measurement of spin correlation in top-antitop quark events and search for top squark pair production in pp collisions at √s=8  TeV using the ATLAS detector

Research output: Contribution to journalJournal articlepeer-review

Published
  • The ATLAS collaboration
Close
Article number142001
<mark>Journal publication date</mark>8/04/2015
<mark>Journal</mark>Physical review letters
Issue number14
Volume114
Number of pages19
Publication StatusPublished
<mark>Original language</mark>English

Abstract

A measurement of spin correlation in tt¯ production is presented using data collected with the ATLAS detector at the Large Hadron Collider in proton-proton collisions at a center-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 20.3  fb−1. The correlation between the top and antitop quark spins is extracted from dilepton tt¯ events by using the difference in the azimuthal angle between the two charged leptons in the laboratory frame. In the helicity basis the measured degree of correlation corresponds to Ahelicity=0.38±0.04, in agreement with the standard model prediction. A search is performed for pair production of top squarks with masses close to the top quark mass decaying to predominantly right-handed top quarks and a light neutralino, the lightest supersymmetric particle. Top squarks with masses between the top quark mass and 191 GeV are excluded at the 95% confidence level.

Bibliographic note

© 2015 CERN, for the ATLAS Collaboration