相关论文: Heavy Quarks and Leptons at $e^+e^-$ Colliders
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 examine how accurately the general HZV couplings, with V=Z,gamma, may be determined by studying e^+e^- --> Hff-bar processes at future e^+e^- linear colliders. By using the optimal-observable method, which makes use of all available…
Total hadron multiplicities and multiplicities of hadrons in events with heavy quarks in $e^+e^-$ annihilation at the energies of LEP-1.5 and LEP-2 are calculated on the basis of QCD.
We discuss associated production of a Higgs boson with a pair of $t {\bar t}$ quarks at a future high energy $e^+e^-$ collider. The process $e^+e^-\to t {\bar t}h$ is particularly sensitive to the presence of new physics and we consider the…
We compute two-loop helicity amplitudes in QCD for diphoton production through quark- and gluon-initiated channels, accounting for a massive internal quark loop by keeping its full mass dependence. Using physical projectors, we directly…
Recently, significant enhancements of $e^{+} e^{-}$ pair production at very low transverse momentum ($p_{T} < 0.15$ GeV/c) were observed by the STAR collaboration in peripheral hadronic A+A collisions. This excesses can not be described by…
The inclusive production of charged hadrons in the collisions of quasi-real photons e+e- -> e+e- +X has been measured using the OPAL detector at LEP. The data were taken at e+e- centre-of-mass energies from 183 to 209 GeV. The differential…
Heavy quark and charmonium production as well as their space-time evolution are studied in transport simulations of heavy-ion collisions at RHIC and LHC. In the partonic transport model Boltzmann Approach of MultiParton Scatterings (BAMPS)…
Heavy quark production has been very well studied over the last years both theoretically and experimentally. Theory has been used to study heavy quark production in $e p$ collisions at HERA, in $pp$ collisions at Tevatron and at RHIC, in…
The physics at an e+e- linear collider with a center of mass energy of 3-5 TeV is reviewed. The following topics are covered: experimental environment, Higgs physics, supersymmetry, fermion pair-production, WW scattering, extra dimensions,…
We elaborate on the production of the Standard Model Higgs particle at high-energy $e^+e^-$ colliders through the reaction $e^+e^- \rightarrow ZH$. Particular emphasis is put on the intermediate mass range. In addition to the signal we…
Heavy quarks, i.e. charm and beauty, are sensitive probes of the medium produced in high-energy heavy-ion collisions. They are produced in the early stage of the collision, mainly in hard partonic scattering processes, and are expected to…
At $e^+e^-$ and $ep$ colliders, the large fluxes of almost on-shell photons accompanying the lepton beams lead to the photoproduction of jets. As the centre-of-mass energy is increased, regions of smaller $x$ in the parton densities are…
The models of large extra compact dimensions, as suggested by Arkani-Hamed, Dimopoulos and Dvali, predict exciting phenomenological consequences with gravitational interactions becoming strong at the TeV scale. Such theories can be tested…
We examine very general four-point interactions arising from new physics and contributing to the Higgs production process e+e- -> HZ. We write all possible forms for these interactions consistent with Lorentz invariance. We allow the…
Current mass limits allow the possibility that squarks may be produced in large numbers at the next generation of linear $e^+e^-$ colliders. In this paper we investigate the prospects for precision studies of squark masses at such…
Data from LEP2 on hadron production in gamma gamma interactions at high pT exceed the predictions of QCD by about an order of magnitude. The amplitude for the process is asymptotically proportional to the sum of the squares of the charges…
We perform a comparative study of the reach of future $e^+e^-$ collider options for the scale of non-resonant new physics effects in the top quark sector, phrased in the language of higher-dimensional operators. Our focus is on the…
It is argued that a multicomponent structure of $e^+e^-$ and $p\bar p$ high energy collisions determines the shapes of multiplicity distributions and oscillations of $H_q$ moments. QCD and convoluted NBD are used for comparison with…
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^-…