Speaker
Paul Langacker
Description
Axigluons have been suggested as a possible explanation of
the Tevatron top asymmetry. I discuss a number of
theoretical issues that one encounters in trying to embed an
axigluon in U(3) X U(3) or U(3)^n groups descending from
classes of string constructions, such as type IIA. These
include anomaly cancellation, the difficulty of generating
Yukawa couplings using the most likely quantum numbers
(they must be induced by higher-dimensional operators),
possible family-nonuniversal magnitudes of couplings, the role
of anomalous U(1) factors, the axigluon width, the decay
modes and signatures of exotics needed for anomaly
cancellation, and FCNC effects.
