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Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Top quark production asymmetries A(FB)t and A(FB)ℓ
Edmond L Berger1, Qing-Hong Cao, Chuan-Ren Chen
1High Energy Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.
Physical Review Letters
|March 10, 2012
Summary
Large asymmetries in top quark and lepton distributions at the Tevatron suggest new physics. Spin correlations between top quarks and leptons indicate a preference for models producing more right-handed top quarks.
Area of Science:
- High Energy Physics
- Particle Physics
- Collider Physics
Background:
- The Tevatron collider has provided significant data on top quark production.
- Forward-backward asymmetries in top quark and charged lepton distributions have been observed.
- Understanding top quark polarization is crucial for probing new physics beyond the Standard Model.
Purpose of the Study:
- To investigate the relationship between top quark and charged lepton forward-backward asymmetries.
- To explore the role of spin correlation and polarization in these observables.
- To test the consistency of Standard Model predictions and search for new physics contributions.
Main Methods:
- Analysis of top quark and charged lepton rapidity distributions from Tevatron data.
- Theoretical study of spin correlations and polarization effects in top quark decays.
- Comparison of experimental asymmetries with predictions from different theoretical models.
Main Results:
- A significant forward-backward asymmetry is observed in both top quark and charged lepton rapidity distributions.
- The study highlights the connection between these asymmetries through spin correlations.
- The observed asymmetries are consistent with models predicting enhanced production of right-handed top quarks.
Conclusions:
- The observed large forward-backward asymmetries are sensitive probes of top quark properties.
- Spin correlations play a key role in linking top quark and lepton distributions.
- Current data favors new physics models that generate a higher rate of right-handed top quark production over left-handed ones.
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