Searches for exotic particles in d+Au collisions at $\sqrt{s_{_{NN}}}=200$~GeV and Au+Au collisions at $\sqrt{s_{_{NN}}}=62.4$~GeV

Exotic particles such as pentaquark states and di-baryons are allowed to exist within the framework of Quantum Chromo Dynamics (QCD). Several experiments reported the evidence for the existence of a pentaquark state, $\Theta^{+}(uudd\bar{s})$, however, several other experiments reported null results. We present results on the search of pentaquark states in d+Au collisions at $\sqrt{s_{_{NN}}} = 200$~GeV and Au+Au collisions at $\sqrt{s_{_{NN}}}=62.4$~GeV from the STAR experiment at RHIC. Statistical significance of our searches will be discussed.