Articulo
Observation of spin correlation in tt̄ events from pp collisions at √s = 7 TeV Using the ATLAS detector
Registro en:
issn:1079-7114
issn:0031-9007
Autor
Anduaga, Xabier Sebastián
Dova, María Teresa
Monticelli, Fernando Gabriel
Tripiana, Martín Fernando
The ATLAS Collaboration
Institución
Resumen
A measurement of spin correlation in tt̄ 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 A<sub>helicity</sub> = 0.40<sup>+0:09</sup><sub>-0.08</sub>, in agreement with the next-to-leading-order standard model prediction. The hypothesis of zero spin correlation is excluded at 5.1 standard deviations. La lista completa de autores que integran el documento puede consultarse en el archivo. Facultad de Ciencias Exactas Instituto de Física La Plata