Related papers: Asymmetric Leptons for Asymmetric Tops
We propose two new observables to measure the charge asymmetry in hadronic top-quark pair production in association with a hard jet. The incline asymmetry, based on the inclination between the planes of initial- and final-state momenta,…
We calculate the forward backward asymmetry of the top-pair production at TEVATRON up to next to leading order (NLO) in the little Higgs model (LHM). We find that the contribution of $Z_H$ can be large enough to make up the gap between…
New vectorlike quarks are predicted in many new physics scenarios beyond the Standard Model~(SM) and could potentially be discovered at the LHC. Based on a simplified model including a singlet vectorlike top partner with charge $2/3$, we…
We study the process of single-top production in association with a charged Higgs boson at the LHC and discuss how top-quark polarization and an azimuthal asymmetry $A_\varphi$ of the charged lepton from top decay can be used in some…
We measure the charge asymmetry $A$ of like-sign dimuon events in 6.1 fb$^{-1}$ of $p\bar{p}$ collisions recorded with the D0 detector at a center-of-mass energy $\sqrt{s} = 1.96$ TeV at the Fermilab Tevatron collider. From $A$, we extract…
The forward LHCb acceptance offers the possibility of measuring the top-quark pair asymmetry in a kinematic region that does not receive overwhelming dilution from the symmetric gluon-fusion channel. To investigate this possibility, two…
We study the potential LHC discovery of the Z1 KK gauge boson unitarizing longitudinal W+W- scattering amplitude. In particular, we explore the decay mode Z1->t tbar along with Z1-> W+W- without specifying the branching fractions. We…
Among different measured observables of top-antitop quark pairs at hadron colliders, the forward-backward asymmetry ($A_{\text{FB}}$) measured by the CDF and D0 collaborations has inconsistency with the Standard Model prediction. The…
Electroweak production of single top quarks is an as-yet-unverified prediction of the Standard model, potentially sensitive to new physics. Two of the single top quark productions channels have significant charge asymmetries at the LHC,…
We investigate the production, signatures and backgrounds of a pair of heavy-exotic charged leptons and a heavy-exotic neutrino together with the exotic charged lepton in the framework of the vector singlet model, vector doublet model, and…
A number of top-spin observables are computed within the Standard Model (SM), at next-to-leading order in the strong and weak gauge couplings for hadronic top-quark anti-quark (ttbar) production and decay at the LHC for center-of-mass…
A recent CMS analysis has reported the observation of an excess in the invariant mass distribution of the opposite-sign same-flavour lepton pair, which can be interpreted as a kinematic edge due to new physics. Using collider simulation…
We use an effective operator framework to study the contributions to the Tevatron t tbar asymmetry from arbitrary vector bosons and scalars, and compare with their effect on the t tbar tail at LHC. Our study shows, for example, that models…
With the next start of LHC, a huge production of top quarks is expected. There are several models that predict the existence of heavy colored resonances decaying to top quarks in the TeV energy range. A peak in the differential cross…
We discuss the potential of AFTER@LHC to measure single-transverse-spin asymmetries in open-charm and bottomonium production. With a HERMES-like hydrogen polarised target, such measurements over a year can reach precisions close to the per…
We study the sensitivity of top pair production at the Large Hadron Collider (LHC) to the nature of an underlying Z' boson, including full tree level standard model background effects and interferences. We demonstrate that exploiting…
We propose a new strategy to probe the $Z$ boson couplings to bottom and charm quarks at the LHC. In this work we mainly focus on the case of bottom quarks. Here, the $Z$ boson is produced in association with two $b$-jets and decays to…
At the LHC, dileptonic events may turn up new physics interacting with quarks and leptons. The poster child for this scenario is a resonant $Z'$, much anticipated in $\ell^+ \ell^-$ invariant mass spectra. However, angular spectra of…
In the quasi-inert Higgs doublet model, we study the LHC diphoton rate for a standard model-like Higgs boson and the top quark forward-backward asymmetry at Tevatron. Taking into account the constraints from the vacuum stability, unitarity,…
Motivated by the persistence of a large measured top quark forward-backward asymmetry at the Tevatron, we examine a model of non-Abelian flavor gauge symmetry. The exchange of the gauge bosons in the $t$-channel can give a large asymmetry…