Related papers: Quark resonances and high E_t jets
We consider top quark pair production in association with a hard jet through next-to-leading order in perturbative QCD. Top quark decays are treated in the narrow width approximation and spin correlations are retained throughout the…
Next-to-leading order calculation for three jet heavy quark production in e^+e^- collisions, including complete quark mass effects, is reviewed. Its applications at LEP/SLC are also discussed.
Heavy quark production in five jet events at $e^+e^-$ colliders is studied at tree level using helicity amplitudes. Total production rates for $2b3j$ and $4bj$ are given and compared with the corresponding results for massless quarks. The…
We present a detailed description of our calculation of next-to-leading order QCD corrections to heavy quark production in e^+ e^- collisions including mass effects. In particular, we study the observables $R_3^{b\ql}$ and $D_2^{b\ql}$ in…
A search is performed for pair-produced spin-3/2 excited top quarks (t* t*-bar), each decaying to a top quark and a gluon. The search uses data collected with the CMS detector from pp collisions at a center-of-mass energy of sqrt(s) = 8…
We consider three jet production at high $p_T$ in the $\gamma\gamma \to q \bar q g$ process and calculate quark and gluon jet spectra. The possibility of quark-gluon jet separation is discussed and compared with the $e^+ e^- \to q \bar q g$…
We report on the calculation of the NLO QCD corrections to top quark pair production in association with two hard jets at the LHC. We take into account higher-order effects in both the production and decays of the top-quark pair. The latter…
Heavy hadron production in $e^+e^-$ annihilation is studied in the framework of heavy-quark recombination mechanism. This mechanism predicts a new type of 3-jet event such as $b\bar{b}q$ or $b\bar{b}\bar{q}$, which is power-suppressed…
A search for the pair production of heavy spin-1/2 or spin-3/2 resonances (t$^*$) in proton-proton collisions at $\sqrt{s}$ = 13 TeV is presented. Data collected with the CMS detector at the CERN LHC from 2016 to 2018 corresponding to an…
A spin-3/2 top quark excitation originating in string realisations of the RS scenario has an effect on the production of top-antitop pairs in hadron-hadron collisions. We study the additional contribution of this state to the cross section…
The CDF collaboration reported an excess in the production of two jets in association with a $W$. We discuss constraints on possible new particle state interpretations of this excess. The fact of no statistically significant deviation from…
Around 1999, thanks to the RHIC Spin Collaboration (RSC), the Relativistic Heavy Ion Collider (RHIC) will be used as a polarized proton-proton collider. A new handed interaction between quark subconstituents, which could explain the excess…
We consider the production of spin 3/2 quarks in hadron-hadron and photon-photon colliders. The cross sections at LHC energy is large enough to observe such exotic quarks up to a mass of a few TeV.
In this talk we review some of the most relevant effects that the mixing with a Q=2/3 quark singlet might give at high energy colliders and K and B factories.
The recently found excess of high E$_T$ jets over current QCD predictions is attributed to gluon radiation at double scattering process inside a nucleon. The order of magnitude estimate of the cross section fits experimental findings rather…
We have completed the next-to-leading order perturbative QCD corrections to the virtual-photon exclusive differential cross sections for heavy quark production in deep-inelastic electron-proton scattering, i.e. $e + P \rightarrow Q +…
We present a search for anomalous production of heavy-flavor quark jets in association with a W boson at the Fermilab Tevatron ppbar Collider. This search is conducted through an examination of the exclusive jet spectrum of W+jets final…
Large extra dimension effects on the spin configuration of the top quark pair at the $e^+ e^-\to t\bar{t}$ process are studied. It is shown that the TeV scale quantum gravity effects cause significant deviations from the Standard Model…
The semi-inclusive decay processes of a top quark into a charged pseudo-scalar meson and a jet are studied within the framework of QCD factorization. The leading power of the decay matrix elements can be factorized into heavy-to-light quark…
This is a brief review of charge asymmetries in top-antitop quark production at the LHC. Proposed asymmetry observables in processes of associated top-pair production $t\bar t$ + jet, $t\bar t + W$, and $t\bar t + \gamma$ are analyzed and…