PRODUCTION OF SIGMA(-) AND XI(-) MEASURED WITH THE DELPHI DETECTOR

The production rate of Sigma(-) in Z(0) decays is measured by DELPHI a nd the result is presented and compared to JETSET. Due to their long d ecay length, the decay of Sigma(+/-) often takes place outside the thr ee-layered microvertex detector, which makes a direct determination of their track parameters possible. A direct measurement of the Xi(-) an d <(Xi)over bar>(+) lifetimes and masses is also presented. The produc tion rate <Xi(-) + Xi(+)>(<q(q)over bar>) in all hadronic events is me asured and compared to the JETSET model as well as the production rate <Xi(-) + <(Xi)over bar>(+)>(<b(b)over bar>) in b<b(b)over bar> events .