Ian-Woo Kim (U. Michigan Ann Arbor)

Tevatron Top A_FB Versus LHC Top Physics

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

Link to the slides.