Exotic hypernuclear systems and heavy ion collisions

Abstract

We discuss perspectives in hypernuclear studies opened by their integration with heavy ion physics. Particularly, neutron–rich Λ hypernuclei and double–Λ hypernucleican be produced, which are hardly attainable by traditional reactions and can enrich our knowledge on hadronic interactions.

Hypernuclei and Antihypernuclei Production in Heavy-Ion Collisions

“…Hypernuclei yields have been measured by ALICE [16], STAR [17], and HypHI [18] in the past. The 3 Λ H yield at mid-rapidity from Pb+Pb collisions at 2.76 TeV measured by AL-ICE are consistent with thermal model predictions [19] and UrQMD [20]. Multi-differential measurements in the production yield of hypernuclei are in different systems are essential in advancing our understanding in the field.…”

“…The hypertriton is a weakly bound object, leading to small overlap between the Λ and the deuteron core. This leads to the theoretical expectation that the 3 Λ H lifetime is close to the free Λ lifetime τ Λ . However, STAR and HypHI has reported lifetimes 30 − 40% shorter than τ Λ .…”

“…5, and are compared to ALICE measurements at 2.76 [16] and 5.02 TeV [5] Pb+Pb collisions, as well as theoretical calculations. The statistical thermal model [19] which incorporates canonical suppression through the introduction of the canonical volume paramter V C , can successfully describe the 3 Λ H yield over few orders of magnitude of √ s NN , while underestimating the 4 Λ H yield at 3 GeV. Similarly, the coalescence (DCM) [20] also describes the 3 Λ H yield at 3 GeV while underestimating 4 Λ H .…”

“…Also, the production mechanisms of light nuclei may be studied, providing input to the Y-N interaction as well as properties of the matter formed. Finally, it has been proposed that exotic hypernuclei may be produced in heavy ion collisions [3]. Recent measurements of hypernuclei in heavy ion collisions provide new input to the Y-N interaction.…”

“…Figure 5. (a)3 Λ H and (b)4 Λ H yields at |y| < 0.5 as a function of beam energy in central heavy ion collisions. The symbols represent measurements while the lines represent different theoretical calculations.…”