Ultraviolet Completions of Axigluon Models and Their Phenomenological Consequences

Understand

The CDF and D0 collaborations have observed a forward-backward asymmetry in t-tbar production at large invariant mass in excess of the standard model prediction.

• One explanation involves a heavy color octet particle with axial vector couplings to quarks (an axigluon).
• We describe and contrast various aspects of axigluons obtained from the breaking of a chiral SU(3)_L x SU(3)_R gauge theory both from the standpoint of a string-inspired field theory and from a quiver analysis of a local type IIa intersecting brane construction.
• Special attention is paid to the additional constraints and issues that arise from these classes of top-down constructions compared with the more common effective field theory approach.