Rights statement: Published by the American Physical Society under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. © 2012 CERN, for the ATLAS Collaboration
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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Observation of Spin Correlation in tt¯ Events from pp Collisions at s√=7 TeV Using the ATLAS Detector
AU - Barton, Adam
AU - Borissov, Guennadi
AU - Bouhova-Thacker, Eva
AU - Brodbeck, Timothy
AU - Chilingarov, Alexandre
AU - Davidson, Ruth
AU - de Mora, Lee
AU - Dearnaley, William
AU - Fox, Harald
AU - Henderson, Robert
AU - Hughes, Gareth
AU - Jones, Roger William Lewis
AU - Kartvelishvili, Vakhtang
AU - Long, Robin
AU - Love, Peter
AU - Ratoff, Peter
AU - Smizanska, Maria
AU - Walder, James
AU - The ATLAS collaboration
N1 - Published by the American Physical Society under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. © 2012 CERN, for the ATLAS Collaboration
PY - 2012/5/24
Y1 - 2012/5/24
N2 - A measurement of spin correlation in tt¯ production is reported using data collected with the ATLAS detector at the LHC, corresponding to an integrated luminosity of 2.1 fb−1. Candidate events are selected in the dilepton topology with large missing transverse energy and at least two jets. The difference in azimuthal angle between the two charged leptons in the laboratory frame is used to extract the correlation between the top and antitop quark spins. In the helicity basis the measured degree of correlation corresponds to Ahelicity=0.40+0.09−0.08, in agreement with the next-to-leading-order standard model prediction. The hypothesis of zero spin correlation is excluded at 5.1 standard deviations.
AB - A measurement of spin correlation in tt¯ production is reported using data collected with the ATLAS detector at the LHC, corresponding to an integrated luminosity of 2.1 fb−1. Candidate events are selected in the dilepton topology with large missing transverse energy and at least two jets. The difference in azimuthal angle between the two charged leptons in the laboratory frame is used to extract the correlation between the top and antitop quark spins. In the helicity basis the measured degree of correlation corresponds to Ahelicity=0.40+0.09−0.08, in agreement with the next-to-leading-order standard model prediction. The hypothesis of zero spin correlation is excluded at 5.1 standard deviations.
U2 - 10.1103/PhysRevLett.108.212001
DO - 10.1103/PhysRevLett.108.212001
M3 - Journal article
VL - 108
JO - Physical review letters
JF - Physical review letters
SN - 1079-7114
IS - 21
M1 - 212001
ER -