Search for weakly decaying Λn‾ and ΛΛ exotic bound states in central Pb–Pb collisions at sNN=2.76 TeV

We present results of a search for two hypothetical strange dibaryon states, i.e. the H-dibaryon and the possible View the MathMLsource bound state. The search is performed with the ALICE detector in central (0–10%) Pb– Pb collisions at View the MathMLsource, by invariant massanalysis in the decay modes View the MathMLsource and H-dibaryon →Λpπ−. No evidence for these bound statesis observed. Upper limits are determined at 99% confidence level for a wide range of lifetimes and for the full range of branching ratios. The results are compared to thermal, coalescence and hybrid UrQMD model expectations, which describe correctly the production of other loosely bound states, like the deuteron and the hypertriton.