(3)(Lambda)H and (3) ((Lambda)over-bar) (H)over-bar production in Pb-Pb collisions at root s(NN)=2.76 TeV Ante;

The production of the hypertriton nuclei 3 (cid:2) H and 3 ¯ (cid:2) H has been measured for the first time in Pb–Pb collisions at √ s NN = 2 . 76 TeV with the ALICE experiment at LHC. The p T -integrated 3 (cid:2) H yield in one unity of rapidity, d N / d y × B . R . (cid:2) 3 (cid:2) H → 3 He , π − (cid:3) = ( 3 . 86 ± 0 . 77 ( stat. ) ± 0 . 68 ( syst. )) × 10 − 5 in the 0–10% most central collisions, is consistent with the predictions from a statistical thermal model using the same temperature as for the light hadrons. The coalescence parameter B 3 shows a dependence on the transverse momentum, similar to the B 2 of deuterons and the B 3 of 3 He nuclei. The ratio of yields S 3 = 3 (cid:2) H /( 3 He × (cid:2)/ p ) was measured to be S 3 = 0 . 60 ± 0 . 13 ( stat. ) ± 0 . 21 ( syst. ) in 0–10% centrality events; this value is compared to different theoretical models. The measured S 3 is compatible with thermal model predictions. The measured 3 (cid:2) H lifetime, τ = 181 + 54 − 39 ( stat. ) ± 33 ( syst. ) ps is in agreement within 1 σ with the world average value. benefit