Upper limit of the rapidity density as function of the decay length shown for the $\overline{\Lambda \mathrm{n}}$ bound state in the upper panel and for the H-dibaryon in the lower panel. Here a branching ratio of 64\% was used for the H-dibaryon and a branching ratio of 54\% for the $\overline{\Lambda \mathrm{n}}$ bound state. The horizontal (dashed) lines indicate the expectation of the thermal model with a temperature of 156 MeV. The vertical line shows the lifetime of the free $\Lambda$ baryon.