Introduction The transition from normal nuclear matter to the Quark- Gluon Plasma (QGP), a hot and dense partonic matter, has been predicted by the Lattice QCD. Relativistic heavy-ion collision creates suitable conditions for the formation of QGP, and indeed, mounting evidences suggest that the QGP matter has been produced in central Au + Au collisions at RHIC's top energies [1-4]. If compared to elementary par- ticle collisions, nuclear collisions deposit large amount of energy into a more extended volume, allowing for the creation of a plasma containing roughly equal numbers of quarks and antiquarks. On the other hand, in contrast to the other extreme-the Big Bang, nuclear collisions produce negligible gravitational attraction and allow the QGP to expand rapidly, As the expansion slows down the plasma undergoes a transition into hadron gas, producing nucleons and their antiparticles. During the process, light antimat- ter nuclei can be formed by thermal production [5] or by coalescence [6]. The high temperature and high antibaryon density of relativistic heavy-ion collisions provide a favor- able environment for both production mechanisms. Once light antimatter nuclei are formed, the relatively short-lived expansion in nuclear collisions allows antimatter to de- couple quickly from matter, and avoid annihilation. Thus relativistic heavy-ion collision is an ideal venue to produce rare antimatter nuclei.
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