Production of Sigma(-) and Lambda(1520) in hadronic Z decays has been measu
red using the DELPHI detector at LEP. The Sigma(-) is directly reconstructe
d as a charged track in the DELPHI microvertex detector and is identified b
y its Sigma --> n pi decay leading to a kink between the Sigma(-) and pi-tr
ack. The reconstruction of the Lambda(1520) resonance relies strongly on th
e particle identification capabilities of the barrel Ring Imaging Cherenkov
detector and on the ionisation loss measurement of the TPC. Inclusive prod
uction spectra are measured for both particles. The production rates are me
asured to be
[NSigma-/N-Z(had)] = 0.081 +/- 0.002 +/- 0.010,
[N-Lambda(1520)/N-Z(had)] = 0.029 +/- 0.005 +/- 0.005.
The production rate of the Lambda(1520) suggests that a large fraction of t
he stable baryons descend from orbitally excited baryonic states. It is sho
wn that the baryon production rates in Z decays follow a universal phenomen
ological law related to isospin, strangeness and mass of the particles. (C)
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