Signature inversion in doubly odd ¹²⁴La

High-spin states have been studied in neutron-deficient ₅₇¹²⁴La₆₇, populated through the ⁶⁴Zn(⁶⁴Zn,3pn) reaction at 260 MeV. The Gammasphere γ-ray spectrometer has been used in conjunction with the Microball charged-particle detector, the Neutron Shell, and the Argonne Fragment Mass Analyzer, in order to select evaporation residues of interest. The known band structures have been extended and new bands found. Most of the bands are linked together, allowing more consistent spin and parity assignments. Comparison of band properties to cranking calculations has allowed configuration assignments to be made and includes the first identification of the g_9/2 proton-hole in an odd-odd lanthanum isotope. Two bands have been assigned a πh_11/2 ⊗ νh_11/2 structure; the yrast one exhibits a signature inversion in its level energies below I = 18.5ℏ, while the excited one exhibits a signature inversion above I = 18.5ℏ.