Related papers: Colour reconnection and Bose-Einstein effects
In the reaction e+e- -> WW -> (q_1 qbar_2)(q_3 qbar_4) the usual hadronization models treat the colour singlets q_1 qbar_2 and q_3 qbar_4 coming from two W bosons independently. However, since the final state partons may coexist in space…
The studies of Fermi-Dirac correlations of $\Lambda\Lambda$ and $\bar{\Lambda}\bar{\Lambda}$ pairs in hadronic $\mathrm{Z}$ decays, Bose-Einstein correlations and colour reconnection in $\mathrm{W}$-pairs decays performed by the ALEPH…
The predicted effects of final state interactions such as colour reconnection are investigated by measuring properties of hadronic decays of W bosons, recorded at a centre-of-mass energy of sqrt(s)=182.7 GeV in the OPAL detector at LEP.…
This report summarises experimental aspects of the phenomena of colour reconnection in W+W- production, concentrating on charged multiplicity and event shapes, which were carried out as part of the Phenomenology Workshop on LEP2 Physics,…
The effects of Final State Interactions(FSI), Colour Reconnection(CR) and Bose--Einstein Correlations(BEC) at small relative momenta of particles are discussed. The short review of the LEP results on BEC at Z-peak, on BEC between particles…
From 1996 up to 2000 the LEP collider at CERN has operated at center of mass energies above the production threshold for W boson pairs of approximately 160 GeV. The obtained data are used to extract a preliminary W mass value of (80.450 +-…
We analyze from a theoretical point of view the impact of various approximations on W mass distributions. This is done both at parton level and after a simulated W mass reconstruction using constrained fits. The results may help to…
A critical summary is given of the present status of the study of Bose-Einstein Correlations in W-pair production at LEP II. In particular, the evidence is reviewed for or against the existence of Bose-Einstein correlations between pions…
An alternative W mass estimator in e+e- -> WW -> qqqq events at LEP2 is designed to optimize the balance between the statistical uncertainty and the systematic uncertainty due to a possible Colour Reconnection effect. The preliminary result…
There are experimental evidence for the occurrence of colour reconnection, but the mechanisms involved are far from understood. Previous reconnection studies are briefly summarized, and some potential implications for LHC physics are…
The mass of the W boson is determined from the direct reconstruction of its decays into purely hadronic and semi-leptonic events in e+e- collisions at LEP. The data sample corresponds to an integrated luminosity of 683 inverse picobarns…
The influence of Bose-Einstein correlations on the determination of the mass of the W boson in e+e- -> WW -> 4jet events at LEP2 energies is studied, using a global event weighting method. We find that it is possible to keep the systematic…
We have investigated some observable consequences of colour reconnection in the reaction e+e- -> W+ W- -> q_1 qbar_2 q_3 qbar_4. We use a measure based on the momentum structure of the event, comparing reconnected events with `standard'…
In the hadronic decay mode of a pair of W bosons, $\text{e}~+\text{e}~- \to \text{W}~+ \text{W}~- \to \text{q}_1 \overline{\text{q}}_2 \text{q}_3 \overline{\text{q}}_4$, QCD interference effects can mix up the two colour singlets…
The W-mass measurements from LEP and the results of a global fit of the Standard Model parameters to the electroweak data are presented. Comprehensive studies of experimental systematic effects allowed a measurement of the W mass with an…
We present new algorithms for simulating Bose-Einstein correlations among final-state bosons in an event generator. The algorithms are all based on introducing Bose-Einstein correlations as a shift of final-state momenta among identical…
One of the most powerful methods for obtaining a precision measurement of M_W at LEP2 is from direct reconstruction of the invariant mass distribution of W bosons produced in e+e- --> W+W-. We investigate the effects on the W line shape,…
We discuss the possibility of colour rearrangement in $\ee \to \W^+ \W^- \to \q_1 \qbar_2 \q_3 \qbar_4$ events, i.e.\ that the original colour singlets $\q_1 \qbar_2$ and $\q_3 \qbar_4$ may be transmuted, for instance, into new singlets…
A search is performed in symmetric 3-jet hadronic Z decay events for evidence of colour singlet production or colour reconnection effects. Asymmetries in the angular separation of particles are found to be sensitive indicators of such…
We show that the presence of residual Bose-Einstein correlations may affect the resonant contribution of hadronic charm decays where two identical pions appear in the final state. The distortion of the phase space of the reaction would be…