Identification of μs-isomers produced in the fragmentation of a ¹¹²Sn beam

Decays of over forty short-lived (T _{1 2} from ≈ 50 ns to 70 μs) isomeric states including a new isomer ^66mAs produced in the fragmentation of a ¹¹²Sn beam (58 A·MeV, 63 A·MeV) on a ^natNi target were observed at the final focus of the LISE3 spectrometer at GANIL. Their detection, based on the slow (≈ 10 μs) time correlation of identified ions with the characteristic γ-radiation, represents a novel method to search for new isomers and can be used for unambiguous isotope identification for projectile fragment separator experiments. Isomeric yields and isomer-to-total production ratios were determined.