相关论文: Off-diagonal Helicity Density Matrix Elements for …
In this work we analyse the theoretical uncertainties on the predictions for the photoproduction of light vector mesons in coherent pp, pA and AA collisions at the LHC energies using the color dipole approach. In particular, we present our…
Several extensions of the Standard Model predict the production of dark matter particles at the LHC. An uncharted signature of dark matter particles produced in association with $VV=W^\pm W^\mp$ or $ZZ$ pairs from a decay of a dark Higgs…
In e^+e^- collisions at centre-of-mass energies around 91 GeV, D^*0 mesons have been reconstructed using data collected with the OPAL detector at LEP. The hadronisation fraction has been measured to be f(c -> D^*0) = 0.218 +/- 0.054 +/-…
The investigation in the work of the reaction electron-positron to omega and pi0 mesons in the 3P0 nonrelativistic quark model reveals that the reaction electron-positron to omega and pi0 mesons process at the energy region from the omega…
The hypothesis is scrutinized that the weak interaction of hadronic systems at low energies is dominated by the coupling of the pseudoscalar, vector, and axial-vector mesons to the weak gauge bosons. The strength of the weak coupling of the…
We search for the technicolor process ppbar -> rho_T/omega_T ->W+pi_T in events containing one electron and two jets, in data corresponding to an integrated luminosity of 390 pb-1, recorded by the D0 experiment at the Fermilab Tevatron.…
A search is presented for production of a heavy up-type quark (t') together with its antiparticle, assuming subsequent decay to a W boson and a b quark, t't'bar -> W+b W-bbar. The search is based on 1.04 fb^-1 of proton-proton collisions at…
The production of the excited charm mesons D_1(2420) and D^*_2(2460) in ep collisions has been measured with the ZEUS detector at HERA using an integrated luminosity of 373 pb^{-1}. The masses of the neutral and charged states, the widths…
Hypothesis of heavy stable quark of 4th family can provide a nontrivial solution for cosmological dark matter if baryon asymmetry in 4th family has negative sign and the excess of anti-U quarks with charge (-2/3) is generated in early…
In this contribution, we present some predictions for the production of D and B mesons in ultrarelativistic heavy ion collisions at RHIC and LHC energies and confront them with experimental results obtained so far by the STAR, PHENIX, ALICE…
Exclusive incoherent electroproduction of the rho^0(770) meson from 1H, 2H, 3He, and 14N targets has been studied by the HERMES experiment at squared four-momentum transfer Q**2>0.4 GeV**2 and positron energy loss nu from 9 to 20 GeV. The…
The e-e+ collider LEP, running at sqrt{s} = m(Z0), has been a copious source of b-hadrons produced in decays Z0 -> b \b. We present recent studies using up to 4*10^6 hadronic Z0 decays acquired by the DELPHI detector between 1992 and 2000.…
In this paper searches are presented for the pair production of first and second generation scalar leptoquarks and limits are given on the quark-lepton compositeness scale from proton-antiproton collision data at a center-of-mass energy…
The H1 and ZEUS collaborations at HERA report new data on the diffractive production of vector mesons with a many-fold increase of luminosity compared to previous measurements. The new data include photoproduction and electroproduction of…
A simple schematic model anchored on the notion of hadronic freedom inferred from hidden local symmetry in the vector manifestation, the infinite tower of vector mesons in holographic QCD and "stickiness" of $\pi\pi$ interactions inferred…
We report on D0 searches for leptoquarks (LQ) predicted in extended gauge theories and composite models to explain the symmetry between quarks and leptons. Data samples obtained with the D0 detector from proton-antiproton collisions at a…
The production of the light vector mesons $V = \rho, \omega, \phi$ in the reactions $\pi N \to V N$ and $N N \to V N N$ near threshold is studied. The subsequent electromagnetic decay $V \to \gamma^* \to e^+ e^-$ is particularly suited for…
We calculate diffractive photo- and leptoproduction of $\rho$-, $\rho'$- and $\rho''$-mesons. The incoming photon dissociates into a $q\bar{q}$-dipole which scatters on the nucleon and transforms into a vector meson state. The scattering…
The results of a search for direct pair production of top squarks and for dark matter in events with two opposite-charge leptons (electrons or muons), jets and missing transverse momentum are reported, using 139 fb$^{-1}$ of integrated…
We report results of experiments performed with the KEDR detector at the VEPP-4M e+e- collider. They include precise measurement of the D0 and D+- meson masses, determination of the psi(3770) resonance parameters, and a search for narrow…