An upper limit on hypertriton production in collisions of Ar(1.76 AGeV)+KCl

A high-statistic data sample of Ar(1.76 AGeV)+KCl events recorded with HADES is used to search for a hypertriton signal. An upper production limit per centrality-triggered event of $1.04$ x $10^{-3}$ on the $3sigma$ level is derived. Comparing this value with the number of successfully reconstructed $Lambda$ hyperons allows to determine an upper limit on the ratio $N_{_{Lambda}^3H}/N_{Lambda}$, which is confronted with statistical and coalescence-type model calculations.