Related papers: Gluon Polarization in $e^+e^-\to t\bar tG$
Heavy quark production is studied at the high energy linear e^+e^- collider (LC) TESLA both in its nominal and Photon Collider (PC) mode. Leading order cross-sections are calculated for the production of heavy quarks, e^+e^- -> e^+e^-…
We study the top-quark pair production via polarized and unpolarized photon collisions at the International Linear Collider in the context of the littlest Higgs model with T-parity. We calculate the production cross section of the process…
The gluon polarisation in the nucleon was measured using open charm production by scattering 160 GeV/c polarised muons off longitudinally polarised protons or deuterons. The data were taken by the COMPASS collaboration between 2002 and…
We calculate the $cos~2 \phi$ asymmetry in $J/\psi$ production in electron-proton collision for the kinematics of the planned electron-ion collider (EIC). This directly probes the Weisz\"acker-Williams (WW) type linearly polarized gluon…
The cross-section for the production of $t\bar{t}$ pairs in $e^+e^-$-annihilation via a virtual photon is determined up to order $\alpha_s^2$. For the cm-energies of interest the effect of the top mass may not be considered as a small…
The emission of the hard photon by the initial state is considered. The nucleon polarization and the differential cross sections for some experimental conditions have been calculated. The case of the emission of the collinear (with respect…
We calculate the classical gluon field of a fast projectile passing through a dense medium. We show that this allows us to calculate both the initial state gluon production in proton-nucleus collisions and the final state gluon radiation…
The color dipole formulation provides an intuitive picture of hard processes in high energy scattering. Most importantly, this approach allows one to calculate nuclear effects in a parameter-free way. I review the relation between the…
In the littlest Higgs model with T-parity, we studied the contributions of the new particles to the top-quark pair production via $e^{+}e^{-}$ collision at the International Linear Collider. We calculated the top-quark pair production cross…
We present theoretical results for the associated production of a single top quark and a $Z$ boson ($tqZ$ production) at LHC energies. We calculate higher-order corrections from soft-gluon emission for this process. We compute the…
We calculate thermal production of u, d, s, c and b quarks in ultra-relativistic heavy ion collisions. The following processes are taken into account: thermal gluon decay (g to ibar i), gluon fusion (g g to ibar i), and quark-antiquark…
Linear e+e- colliders provide a rich set of opportunities for top quark physics, crucial for the understanding of electroweak symmetry breaking and for the search for physics beyond the Standard Model. A ttbar threshold scan in e+e-…
We study the polarization of hyperon in different processes in singly polarized $pp$ collisions, in particular its relation to the polarized parton distributions. We show that by measuring hyperon polarization in particularly chosen…
We examine a method of studying the Z polarization in $H\to ZZ \to \ell^+ \ell^- \nu \bar{\nu}$ in proton-proton collisions at the Large Hadron Collider (LHC). Included are the dominant contributions: gluon fusion production of the Higgs…
The $e^+e^-$ pair production in collisions of muon with atoms is considered to all orders in the parameter $Z\alpha$. We obtain energy distribution of $e^+$ and $e^-$ as well as energy loss of muon passing through matter with heavy atoms.…
We compute the probabilty for the processes A -> q \bar{q}, gg via vacuum polarization in the presence of a classical space-time dependent non-abelian field A by applying the background field method of QCD. The processes we consider are…
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…
We derive a high energy factorization theorem for inclusive gluon production in A+A collisions. Our factorized formula resums i) all order leading logarithms (g^2 \ln(1/x_{1,2}))^n of the incoming partons momentum fractions, and ii) all…
The gluon collision process that creates a heavy-quark-antiquark pair with small relative momentum and large transverse momentum predicts at leading-order in the QCD coupling constant that the transverse polarization of the pair should…
The sensitivity to the $Z^\prime$ couplings of the processes $e^+e^-\to l^+l^-,\bar{b}b$ and $\bar{c}c$ at the linear collider with $\sqrt{s}=500 GeV$ with initial beam polarization, for typical extended model examples are studied. To this…