Measuring the bottom-quark forward-central asymmetry at the LHC

Abstract

Measurements of the top quark forward-backward asymmetry performed at the Tevatron suggest that new-physics may be playing a role in t-tbar production. To better understand the source of the asymmetry, recent proposals have called for a measurement of the bottom and charm forward-backward asymmetries at the Tevatron, using jets with embedded muons. Here we propose a corresponding measurement of the bottom quark forward-central asymmetry designed to look for similar effects in the b-sector at ATLAS and CMS. We construct a set of cuts designed to enhance sensitivity to this asymmetry, and test our analysis on a toy axigluon model representative of those used to explain the top asymmetry. We find that if the relevant new-physics couplings to the bottom quark are similar to those of the top, then the effects should be visible at the two sigma level in less than 10 fb-1 of 7 TeV LHC data. Such a measurement would be of general importance, and would provide valuable model-building input, serving to restrict the set of models put forward to explain the Tevatron t-tbar anomaly. However, a relatively low trigger threshold on non-isolated muons inside hard jets must be maintained to allow for this measurement.