Ian-Woo Kim (U. Michigan Ann Arbor)
We carry out a comprehensive analysis of models for top A_FB at CDF
in light of new top data arriving from the LHC. We begin with a careful
Tevatron analysis, considering in general which sets of effective vertices
give rise to a large forward-backward asymmetry while suppressing the
contribution to the total t tbar cross-section. We show on general grounds
that scalar models struggle to produce sufficient asymmetries consistent
with CDF observations, while vector models can produce a large asymmetry
with a less significant tension in the total cross-section and ttbar invariant
mass distribution at the Tevatron. We examine the essential observables
of these models for top physics at LHC7 with 1 fb^-1 of data, including
the total cross-section, invariant mass distribution and number of additional
jets in ttbar events. In the case of t-channel mediators, the LHC total
cross-section places a strong constraint on light mediators, while
the Tevatron invariant mass distributions place strong constraints
on heavy mediators that are able to produce the asymmetry.
Heavy axigluons are becoming increasingly squeezed by LHC7
ttbar and dijet resonance searches. We conclude that LHC7 top analyses
are rapidly closing the window for viable models of the CDF top A_FB.
Oct 10 at 4pm in Geo/Phys Room 407