Related papers: Transverse beam polarization and limits on leptoqu…
The production of high-transverse energy jets in hadron-hadroncollisions is sensitive to the presence of new contact interactions between quarks. If proton polarization were available, the measurement of some parity violating spin…
We present the leading order unpolarized and polarized cross sections in electroweak semi-inclusive deep inelastic leptoproduction. The azimuthal dependences in the cross section differential in the transverse momentum of the vector boson…
Electroweak production of the top quark is measured in pp collisions at sqrt(s) = 7 TeV, using a dataset collected with the CMS detector at the LHC and corresponding to an integrated luminosity of 36 inverse picobarns. With an event…
In this paper we study the azimuthal correlations of heavy quarks in Pb+Pb collisions with $\sqrt{s}=2.76$ TeV at LHC. Due to the interaction with the medium heavy quarks and antiquarks are deflected from their original direction and the…
The results of a first search for CP violation in the production and decay of top quark-antiquark (t t-bar) pairs are presented. The search is based on asymmetries in T-odd, triple-product correlation observables, where T is the…
We demonstrate that the ability to polarize the photons produced by back-scattering laser beams at a TeV scale linear $\epem$ collider could make it possible to determine whether or not a neutral Higgs boson produced in photon-photon…
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…
The possibility of observing CP-violation in the process $\gamma \gamma \to H$ is investigated for masses of the Higgs particle in the interval $M_z \lsim m_H \lsim 2 m_t$, using a 0.5TeV tunable linear $e^{+} e^{-}$ collider through laser…
We study pair production of leptoquarks in e+e- annihilation at linear colliders. A detailed simulation including beamstrahlung and initial state radiation, leptoquark decay and hadronization, as well as detector smearing, is performed.…
We study selectron production at an e-e- linear collider. With the help of transverse beam polarizations, we define CP sensitive observables in the production process e- e- --> selectron_L selectron_R. This process proceeds via t-channel…
We report on an investigation of CP violation in (un)polarized $e^+e^-\to{\bar t}t$ resulting from an extended neutral Higgs sector or from the minimal SUSY extension of the Standard Model (SM). We consider c.m. energies from the ${\bar…
Large parity violating longitudinal single spin asymmetries A^{e^-}_L= -0.86^{+0.14}_{-0.30} and A^{e^+}_L= 0.88^{+0.12}_{-0.71} are observed for inclusive high transverse momentum electrons and positrons in polarized pp collisions at a…
We study leptoquark production using polarized $e\gamma$ colliders for the center of mass energies $\sqrt s=500$~GeV and 1~TeV. We show that using polarization asymmetries the ten different types of leptoquarks listed by Buchm\"uller,…
In order to observe a signal of possible CP violation in top-quark couplings, we have studied energy correlation of the final leptons in $e^+e^-\to t\bar{t} \to \ell^+\ell^-X / \ell^\pm X$ at future linear colliders. Applying the…
The International Linear Collider (ILC) will be able to precisely measure the electroweak couplings of the top in e+e- -> tt~. We compare the limits which can be achieved at the ILC with those which can be obtained in tt~gamma$ and tt~Z…
The Tevatron, where the top quark was discovered, and the currently functional Large Hadron Collider (LHC), with copiously produced top pairs, enable a detailed study of top-quark properties. In particular, they can be used to test the…
Possible $CP$-violation in top-quark couplings is discussed. It is shown that the lepton-energy distributions in $e^+ e^- \to t\bar{t} \to \ell^+\ell^-X / \ell^\pm X$ at next linear colliders (NLC) could give us useful information for this…
At a future linear collider, a polarized electron beam will play an important role in interpreting new physics signals. Backgrounds to a new physics reaction can be reduced by choice of the electron polarization state. The origin of a new…
Beam polarization at e+ e- linear colliders will be a powerful tool for high precision analyses. Often it is assumed that the full information from polarization effects is provided by polarization of the electron beam and no further…
We discuss T-odd correlations between jet and lepton momenta in tt_bar events at the Tevatron that can be used to search for CP violation. We identify correlations suitable for the lepton plus jets and purely hadronic top-quark pair decay…