New physics at a high scale λ can affect top-related observables at O(1/λ2) via the interference of effective four quark operators with the SM amplitude. The (ūγμγ5Tau)(t̄γμγ5Tat) operator modifies the large Mtt̄ forward-backward asymmetry, and can account for the recent CDF measurement. The (ūγμTau)(t̄γμTat) operator modifies the differential cross section, but cannot enhance the cross section of ultra-massive boosted jets by more than 60%. The hint for a larger enhancement from a recent CDF measurement may not persist future experimental improvements, or may be a QCD effect that is not accounted for by leading order and matched Monte Carlo tools or naive factorization. If it comes from new physics, it may stem from new light states or an O(1/λ4) new physics effect.
|Number of pages||6|
|Journal||Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics|
|Publication status||Published - 2011 Aug 26|
ASJC Scopus subject areas
- Nuclear and High Energy Physics