Hyperon production in Ar+KCl collisions at 1.76A GeV

We present transverse momentum spectra, rapidity distribution and multiplicity of \( \Lambda\) -hyperons measured with the HADES spectrometer in the reaction Ar(1.76AGeV) + KCl . The yield of \( \Xi^{{-}}_{}\) is calculated from our previously reported \( \Xi^{{-}}_{}\)/(\( \Lambda\) + \( \Sigma^{{0}}_{}\)) ratio and compared to other strange particle multiplicities. Employing a strangeness balance equation the multiplicities of the yet unmeasured \( \Sigma^{{\pm}}_{}\) -hyperons can be estimated. Finally a statistical hadronization model is used to fit the yields of \( \pi^{-}_{}\) , K+, K 0 s , K-, \( \phi\) , \( \Lambda\) and \( \Xi^{-}_{}\) . The resulting chemical freeze-out temperature of T = (76±2) MeV is compared to the measured slope parameters obtained from fits to the transverse mass distributions of the different particles.