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Title: Evidence for Spin Correlation in t(t)over-bar Production

Journal Article · · Physical Review Letters
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We present a measurement of the ratio of events with correlated t and {bar t} spins to the total number of t{bar t} events. This ratio f is evaluated using a matrix-element-based approach in 729 t{bar t} candidate events with a single lepton {ell} (electron or muon) and at least four jets. The analyzed p{bar p} collisions data correspond to an integrated luminosity of 5.3 fb{sup -1} and were collected with the D0 detector at the Fermilab Tevatron collider operating at a center-of-mass energy {radical}s = 1.96 TeV. Combining this result with a recent measurement of f in dileptonic final states, we find f in agreement with the standard model. In addition, the combination provides evidence for the presence of spin correlation in t{bar t} events with a significance of more than 3 standard deviations.

Research Organization:
Brookhaven National Lab. (BNL), Upton, NY (United States)
Sponsoring Organization:
USDOE SC OFFICE OF SCIENCE (SC)
DOE Contract Number:
DE-AC02-98CH10886
OSTI ID:
1037724
Report Number(s):
BNL-97115-2012-JA; KA1101021; TRN: US1201690
Journal Information:
Physical Review Letters, Vol. 108, Issue 3; ISSN 0031-9007
Country of Publication:
United States
Language:
English

References (27)

Angular correlations in top quark pair production and decay at hadron colliders journal May 1996
Maximizing spin correlations in top quark pair production at the Tevatron journal October 1997
Production and decay properties of ultra-heavy quarks journal November 1986
Determination of the Width of the Top Quark journal January 2011
Top quark pair production and decay at hadron colliders journal July 2004
QCD-corrected spin analysing power of jets in decays of polarized top quarks journal July 2002
Spin Correlation in t t ¯ Production from p p ¯ Collisions at √ s = 1.8 TeV journal July 2000
Measurement of t t ¯ spin correlation in p p ¯ collisions using the CDF II detector at the Tevatron journal February 2011
Measurement of spin correlation in <mml:math altimg="si1.gif" overflow="scroll" xmlns:xocs="http://www.elsevier.com/xml/xocs/dtd" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.elsevier.com/xml/ja/dtd" xmlns:ja="http://www.elsevier.com/xml/ja/dtd" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:tb="http://www.elsevier.com/xml/common/table/dtd" xmlns:sb="http://www.elsevier.com/xml/common/struct-bib/dtd" xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:cals="http://www.elsevier.com/xml/common/cals/dtd"><mml:mi>t</mml:mi><mml:mover accent="true"><mml:mi>t</mml:mi><mml:mo>¯</mml:mo></mml:mover></mml:math> production using dilepton final states journal August 2011
Measurement of Spin Correlation in t t ¯ Production Using a Matrix Element Approach journal July 2011
The upgraded DØ detector
  • Abazov, V. M.; Abbott, B.; Abolins, M.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 565, Issue 2 https://doi.org/10.1016/j.nima.2006.05.248
journal September 2006
Measurement of the top quark pair production cross section in the lepton + jets channel in proton-antiproton collisions at s = 1.96     TeV journal July 2011
b-Jet identification in the D0 experiment
  • Abazov, V. M.; Abbott, B.; Abolins, M.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 620, Issue 2-3 https://doi.org/10.1016/j.nima.2010.03.118
journal August 2010
Matching NLO QCD computations and parton shower simulations journal June 2002
New Generation of Parton Distributions with Uncertainties from Global QCD Analysis journal July 2002
HERWIG 6: an event generator for hadron emission reactions with interfering gluons (including supersymmetric processes) journal January 2001
ALPGEN, a generator for hard multiparton processes in hadronic collisions journal July 2003
High-energy-physics event generation with Pythia 6.1 journal April 2001
CompHEP 4.4—automatic computations from Lagrangians to events
  • Boos, E.; Bunichev, V.; Dubinin, M.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 534, Issue 1-2 https://doi.org/10.1016/j.nima.2004.07.096
journal November 2004
Matching matrix elements and shower evolution for top-pair production in hadronic collisions journal January 2007
The matrix element method and its application to measurements of the top quark mass
  • Fiedler, Frank; Grohsjean, Alexander; Haefner, Petra
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 624, Issue 1 https://doi.org/10.1016/j.nima.2010.09.024
journal December 2010
Top quark spin correlations at the Tevatron and the LHC journal May 2011
Measurement of color flow in t t ¯ events from p p ¯ collisions at s = 1.96     TeV journal May 2011
Unified approach to the classical statistical analysis of small signals journal April 1998
Theoretical status and prospects for top-quark pair production at hadron colliders journal August 2008
Measuring the running top-quark mass journal September 2009
HATHOR – HAdronic Top and Heavy quarks crOss section calculatoR journal April 2011

Cited By (10)

A set of top quark spin correlation and polarization observables for the LHC: Standard Model predictions and new physics contributions journal December 2015
Top quark and leptonic charge asymmetries for the Tevatron and LHC journal August 2012
Study of top quark production and decays involving a tau lepton at CDF and limits on a charged Higgs boson contribution journal May 2014
Measurement of the correlation between the polar angles of leptons from top quark decays in the helicity basis at s = 7     T e V using the ATLAS detector journal January 2016
Measurements of t t ¯ spin correlations and top quark polarization using dilepton final states in p p collisions at s = 8     TeV journal March 2016
Top quark physics at the Tevatron using t t ¯ events journal March 2012
Asymmetries in top quark pair production at hadron colliders journal May 2015
Top Quark Physics at the lhc: a Review of the First two Years journal June 2012
Top Quark Physics, an Experimental Perspective journal July 2013
Review of Tevatron results: Top quark physics journal February 2015

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Related Subjects

43 PARTICLE ACCELERATORS
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
FERMILAB TEVATRON
LEPTONS
LUMINOSITY
PRODUCTION
SPIN
STANDARD MODEL