Related papers: Explaining the t-tbar asymmetry with a light axigl…
We present a class of warped extra dimension (composite Higgs) models which conjointly accommodates the t\bar t forward-backward asymmetry observed at the Tevatron and the direct CP asymmetry in singly Cabibbo suppressed D decays first…
We present a search for pair production of a fourth generation t' quark and its antiparticle, followed by their decays to a W boson and a jet, based on an integrated luminosity of 5.3/fb of proton-antiproton collisions at sqrt{s}=1.96 TeV…
We report a measurement of the ttbar production cross section using the CDF II detector at the Fermilab Tevatron. The data consist of events with an energetic electron or muon, missing transverse energy, and three or more hadronic jets, at…
In this report a new search for a narrow-width heavy resonance decaying into top quark pairs (X -> ttbar) in ppbar collisions at sqrt(s)=1.96 TeV has been performed using data collected by the D0 detector at the Fermilab Tevatron collider.…
A gauge model with chiral color symmetry of quarks is considered and possible effects of the color $G'$-boson octet predicted by this symmetry are investigated. The contributions of the $G'$-boson to the cross section $\sigma_{t\bar{t}}$…
Recent measurements of the top quark forward-backward asymmetry at the Tevatron could hint at new physics with an unexpected flavor structure. The significance of such an abnormal flavor structure in alleviating the tension between the…
We argue that the QCD axion can arise from many aligned axions with decay constants much smaller than the conventional axion window. If the typical decay constant is of {\cal O}{(100)} GeV to 1 TeV, one or more of the axions or saxions may…
A measurement of the cross section for the production of top quark-antiquark pairs (t tbar) in association with a vector boson V (W or Z) in proton-proton collisions at sqrt(s) = 8 TeV is presented. The results are based on a dataset…
Both CDF and D0 at Tevatron reported the measurements of forward-backward asymmetry in top pair production, which showed possible deviation from the standard model QCD prediction. In this paper, we show that a new color-octet massive vector…
The t t-bar production cross section (sigma[t t-bar]) is measured in proton-proton collisions at sqrt(s) = 7 TeV in data collected by the CMS experiment, corresponding to an integrated luminosity of 2.3 inverse femtobarns. The measurement…
The $t$-channel exchange of two gluons in a color singlet state represents the lowest order approximation to the Pomeron. This exchange mechanism is thought to also explain the formation of rapidity gaps in dijet events at the Tevatron. At…
We analyze the CMS-reported t tbar excess within conventional Two-Higgs-Doublet Models of Types I, II, X, and Y, using the best-fit pseudoscalar parameters MA = 365 GeV, GammaA over MA = 2 percent, and tan beta = 1.28. Applying theoretical…
Quark-quark and quark-lepton searches for compositenss at the Fermilab Tevatron are summarized. These are of the contact-interaction variety where sqrt(s-hat) < the hypothesized mass scales, Lambda. Tevatron experiments limit a variety of…
The Standard Model provides an excellent description of the observables measured at high energy lepton and hadron colliders. However, measurements of the forward-backward asymmetry of the bottom quark at LEP suggest that the effective…
We present a simultaneous measurement of the forward-backward asymmetry and the top-quark polarization in $t\bar t$ production in dilepton final states using 9.7 fb$^{-1}$ of proton-antiproton collisions at $\sqrt{s}=1.96$ TeV with the D0…
We consider a 5D extension of the DFSZ axion model that addresses both the axion quality and fermion mass hierarchy problems, and predicts flavour-dependent, off-diagonal axion-fermion couplings. The axion is part of a 5D complex scalar…
A simple explanation of the W+dijet excess recently reported by the CDF collaboration involves the introduction of a new gauge boson with sizable couplings to quarks, but with no or highly suppressed couplings to leptons. Anomaly-free…
A measurement is presented of the t t-bar cross section (sigma[ttbar]) in proton-proton collisions at a centre-of-mass energy of 7 TeV, in the all-jet final state that contains at least six jets, two of which are tagged as originating from…
Heavy quarks provide a new dimension to QCD, allowing tests of fundamental theory, the nature of color confinement, and the production of new exotic multiquark states. I also discuss novel explanations for several apparently anomalous…
We reinterpret two recent LHC searches for events containing four top quarks ($t\bar{t}t\bar{t}$) in the context of supersymmetric models with Dirac gauginos and color-octet scalars (sgluons). We explore whether sgluon contributions to the…