The DELPHI detector at LEP has collected 54 pb −1 of data at a centre-of-mass energy around 183 GeV during 1997, 158 pb −1 around 189 GeV during 1998, and 187 pb −1 between 192 and 200 GeV during ...1999. These data were used to measure the average charged particle multiplicity in e + e − →b b ̄ events, 〈n〉 b b ̄ , and the difference δ bl between 〈n〉 b b ̄ and the multiplicity, 〈n〉 l l ̄ , in generic light quark (u,d,s) events: δ bl (183 GeV) =4.55±1.31( stat )±0.73( syst ) , δ bl (189 GeV) =4.43±0.85( stat )±0.61( syst ) , δ bl (200 GeV) =3.39±0.89( stat )±1.01( syst ) . This result is consistent with QCD predictions, while it is inconsistent with calculations assuming that the multiplicity accompanying the decay of a heavy quark is independent of the mass of the quark itself. (Elsevier)
The study of the directional dependence of two-particle correlations in the hadronic decays of the $Z^0$ boson is performed using the data collected by the DELPHI experiment in the 1992--1995 running ...periods. The comparison between the transverse, $R_{\perp}$, and longitudinal, $R_{\parallel}$, correlation radii confirms the string model prediction that the transverse correlation length is smaller than the longitudinal one, with the measured values of $R_{\perp}=0.53\pm 0.08\,\mathrm{fm}$ and $R_{\parallel}=0.85\pm 0.08\,\mathrm{fm}$, for selected $Z^0\rightarrow q\bar{q}$ events.
The rapidity-rank structure of \ppb pairs is used to analyze the mechanism of baryon production in hadronic \zz decay. The relative occurrence of the rapidity-ordered configuration \pmpb, where $M$ ...is a meson, and that of \ppb adjacent pairs is compared. The data are found to be consistent with predictions from a mechanism producing adjacent-rank \ppb pairs, without requiring `string-ordered' \pmpb configurations. An upper limit of 15\% at 90\% confidence is determined for the \pmpb contribution.
We conclude our study of the term “communication” with questions raised by the definition. By what means does human communication differ from the communication between animals or between humans and ...machines? Does communication not imply a subject, someone endowed with interiority? Is it possible to describe what happens between two people? Can we call a machine intelligent? We also can draw the borderlines of the notion. For example, communication often requires language and our analysis of communication is only a very small part of a vast unit.
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