Search for Muonic Atoms at RHIC

We present the search results for muonic atoms on $\sqrt{s_{NN}}=200$ GeV Au+Au collisions collected by the STAR experiment at RHIC. With the muon identification at low momentum, the invariant mass spectra were reconstructed. Clear signals are observed at the expected atom masses. Two particle correlations show that the production of the daughter particles happens at the same space-time point, presenting the signature of atom ionization. The fraction of primordial muons is extracted from $\pi$-$\mu$ correlations.