2010/12/30 by The CDF Collaboration, T. Aaltonen, B. Álvarez González +102 · 1 citation
Engineering · Materials Science · Physics and Astronomy · #High-Energy Particle Collisions Research #Metallurgical Processes and Thermodynamics #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #Solidification and crystal growth phenomena #hep-ex
paper · pdf · doi:10.1103/physrevd.83.112003
published as Phys.Rev.D83:112003,2011 · 23 pages, 18 figures, submitted to Physical Review D
arxiv created 2010/12/30 · openalex publication_date 2011/06/08 · arxiv updated 2011/06/24 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/04
We present a new measurement of the inclusive forward-backward tt production asymmetry and its rapidity and mass dependence. The measurements are performed with data corresponding to an integrated luminosity of 5.3 fb^\ensuremath-1 of pp collisions at √(s)=1.96 TeV, recorded with the CDF-II Detector at the Fermilab Tevatron. Significant inclusive asymmetries are observed in both the laboratory frame and the tt rest frame, and in both cases are found to be consistent with CP conservation under interchange of t and t. In the tt rest frame, the asymmetry is observed to increase with the tt rapidity difference, \ensuremathΔy, and with the invariant mass M_tt of the tt system. Fully corrected parton-level asymmetries are derived in two regions of each variable, and the asymmetry is found to be most significant at large \ensuremathΔy and M_tt. For M_tt\ensuremath≥450 GeV/c2, the parton-level asymmetry in the tt rest frame is A^tt=0.475\ifmmode±\else\textpm\fi0.114 compared to a next-to-leading order QCD prediction of 0.088\ifmmode±\else\textpm\fi0.013.