HAL : in2p3-00004112, version 1
 Physics Letters B 475 (2000) 429-447
 Inclusive $\Sigma^-$ and $\Lambda(1520)$ production in hadronic Z decays
 DELPHI Collaboration(s)
 (2000)
 Production of $\sm$ and $\lft$ in hadronic Z decays has been measuredusing the \delphi detector at \lep. The $\sm$ is directly reconstructed as acharged track in the \delphi microvertex detector and is identified by its$\sdec$ decay leading to a kink between the $\sm$ and $\pi$-track.The reconstruction of the $\lft$ resonance relies strongly on theparticle identification capabilities of the barrel Ring Imaging Cherenkovdetector and on the ionisation loss measurement of the TPC.Inclusive production spectra are measured for both particles.The production rates are measured to be\begin{eqnarray*}\langle N_{\sm}/N_{\rm Z}^{\rm had} \rangle &=& 0.081 \pm 0.002 \pm 0.010~, \\ \langle N_{\lft}/N_{\rm Z}^{\rm had} \rangle &=& 0.029 \pm 0.005 \pm 0.005~.\end{eqnarray*}%The comparably large production rate of the $\lft$ suggestsThe production rate of the $\lft$ suggests that a large fraction of the stable baryons descend from orbibaryonic states.It is shown that the baryon production rates in Z decays follwa universal phenomenological law related to isospin, strangendmass of the particles.
 Thème(s) : Physique/Physique des Hautes Energies - Expérience
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 in2p3-00004112, version 1 http://hal.in2p3.fr/in2p3-00004112 oai:hal.in2p3.fr:in2p3-00004112 Contributeur : Sylvie Florès <> Soumis le : Lundi 13 Mars 2000, 10:34:04 Dernière modification le : Mercredi 23 Août 2006, 09:58:31