Related papers: Probing colour separate singlet states in $e^+ e^-…
We consider the production and decay of selectrons and charginos in $e^-e^-$ collisions. The advantage over usual $e^+e^-$ collisions is the very low level of standard model backgrounds which should make the discovery of selectrons or…
An essential part of high-energy hadronic collisions is the soft hadronic activity that underlies the primary hard interaction. It includes soft radiation from the primary hard partons, secondary multiple parton interactions (MPI), and…
Studies of hadronic final states of $e^+e^-$ annihilations, observed at the Large Electron Positron Collider LEP at CERN, are reviewed. The topics included cover measurements of $\alpha_s$, hadronic event shapes and hadronisation studies,…
In some new physics models, there exists a long-lived colored particle. Although such a particle is expected be discovered by studying the muon-like tracks, it is not easy to discriminate hadronic events from leptonic ones at the Large…
In-medium production of leading hadrons in hard reactions, carrying the main fraction of the jet momentum, involves two stages: (i) the parton originated from the hard process propagates through the medium radiating gluons due to the…
Colour coherence affects the radiation pattern of hard partons both in vacuum and in a dense coloured background formed in heavy ion collisions. In vacuum evolution it leads to the well-known phenomenon of angular ordering, and in heavy ion…
We outline a proof of factorization in exclusive processes, taking into account the presence of soft and collinear modes of arbitrarily low energy, which arise when the external lines of the process are taken on shell. Specifically, we…
We report the first observation of $e^+e^-$ annihilations into states of positive $C$-parity, namely $\rho^0 \rho^0$ and $\phi\rho^0$. The two states are observed in the $\pip\pim\pip\pim$ and $K^+K^-\pip\pim$ final states, respectively, in…
In the past two decades, a plethora of hadronic states beyond the conventional quark model of $q\bar{q}$ mesons and $qqq$ baryons have been observed experimentally, which motivated extensive studies to understand their nature and the…
Efforts to observe color transparency in the reactions: (e,e'p), (p,pp) and coherent nuclear diffractive dissociation of pions into two jets are reviewed.
There exist several classes of theories beyond the Standard Model which contain massive spin-1 color octets, generically called "colorons". Indeed we argue that colorons inevitably appear in the spectrum whenever new colored particles feel…
A review of current experimental results on exclusive hadronic decays of bottom mesons to a single or double charmed final state is presented. We concentrate on branching fraction measurements conducted at $e^+e^-$ colliders at the…
Measurements of heavy quark production in electron-positron collisions are used to analyse the strong interactions between quarks and anti-quarks. A scaling behaviour is observed in distributions of the rapidity change of D*, B*, and B…
The current status of tests of the theory of strong interactions, Quantum Chromo Dynamics (QCD), with data from hadron production in e^+e^- annihilation experiments is reviewed. The LEP experiments ALEPH, DELPHI, L3 and OPAL have published…
In this paper we extend the color dipole formalism to the study of exclusive processes associated with a leading neutron in $ep$ collisions at high energies. The exclusive $\rho$, $\phi$ and $J/\Psi$ production, as well as the Deeply…
High intensity back-scattered laser beams will allow the efficient conversion of a substantial fraction of the incident lepton energy into high energy photons, thus significantly extending the physics capabilities of an electron-electron or…
We consider the asymptotic behavior of the (one dimensional) two-species annihilation reaction A + B --> 0, where both species have a uniform drift in the same direction and like species have a hard core exclusion. Extensive numerical…
A new signal is proposed for the colour reconnection in the hadronic decay of W+ W- in e+e- collisions. Using Pythia Monte Carlo it is shown that this signal, being based on the factorial correlator, is more sensitive than the ones using…
In this Report, QCD results obtained from a study of hadronic event structure in high energy e^+e^- interactions with the L3 detector are presented. The operation of the LEP collider at many different collision energies from 91 GeV to 209…
In the study of multiple scattering of partons in hadron-hadron collisions the possibility of a hard inelastic process at the parton level is included in its simplest possible way, $i.e.$ including the $2 \to 3$ transition. The specific…