TY - JOUR
T1 - Implications of the CDF tt̄ forward-backward asymmetry for boosted top physics
AU - Blum, Kfir
AU - Delaunay, Cédric
AU - Gedalia, Oram
AU - Hochberg, Yonit
AU - Lee, Seung J.
AU - Nir, Yosef
AU - Perez, Gilad
AU - Soreq, Yotam
N1 - Funding Information:
We thank Raz Alon, Yochay Eshel, Alex Kagan, Fabrizio Margaroli, Pekka Sinervo and George Sterman for useful discussions. YN is the Amos de-Shalit chair of theoretical physics and supported by the Israel Science Foundation (grant # 377/07 ), the German–Israeli Foundation for scientific research and development (GIF), and the United States–Israel Binational Science Foundation (BSF) . GP is the Shlomo and Michla Tomarin career development chair and is supported by the Israel Science Foundation (grant # 1087/09 ), EU-FP7 Marie Curie , IRG fellowship , Minerva and G.I.F. , the German–Israeli Foundations , and the Peter & Patricia Gruber Award.
PY - 2011/8/26
Y1 - 2011/8/26
N2 - 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.
AB - 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.
UR - http://www.scopus.com/inward/record.url?scp=80051575630&partnerID=8YFLogxK
U2 - 10.1016/j.physletb.2011.07.020
DO - 10.1016/j.physletb.2011.07.020
M3 - Article
AN - SCOPUS:80051575630
SN - 0370-2693
VL - 702
SP - 364
EP - 369
JO - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
JF - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
IS - 5
ER -