Anti-d and Anti-He Production in Au+Au Collisions at RHIC

Ultra-relativistic Au+Au collisions at RHIC ($\sqrt{s}$=130, 200 GeV) are used to study production of rare anti-nuclei. These clusters of anti-nucleons are formed by coalescence, i.e. overlapping wave functions of anti-nucleons. The coalescence coefficients $B_2$ for Anti-$d$ and $B_3$ for Anti-$^3He$ are determined, and used to derive the fireball radius.