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Updated: May 8, 2026

Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Bottom-quark forward-backward asymmetry in the standard model and beyond
Benjamín Grinstein1, Christopher W Murphy
1Department of Physics, University of California, San Diego, La Jolla, California 92093, USA. bgrinstein@ucsd.edu
Abstract:
We computed the bottom-quark forward-backward asymmetry at the Tevatron in the standard model (SM) and for several new physics scenarios. Near the Z pole, the SM bottom asymmetry is dominated by tree level exchanges of electroweak gauge bosons. While above the Z pole, next-to-leading order QCD dominates the SM asymmetry as was the case with the top-quark forward-backward asymmetry. Light new physics, M(NP)≲150 GeV, can cause significant deviations from the SM prediction for the bottom asymmetry. The bottom asymmetry can be used to distinguish between competing new physics (NP) explanations of the top asymmetry based on how the NP interferes with s-channel gluon and Z exchange.
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