High-k structures in ¹²⁴Cs

High spin states in the odd-odd nucleus ¹²⁴Cs have been investigated through the fusion-evaporation reaction ¹¹⁶Sn( ¹¹B, 3n) ¹²⁴Cs with a beam energy of 45 MeV. A new rotational band is established and assigned as the high-k configuration of πg _9/2[404]9/2 ⁺⊗νh _11/2[523]7/2 ^-. Some structures linking to this band have also been observed. According to the results of the excitation energy systematics, the lowest level of this band is assigned as 9 ^-, and the 8 ^- isomer bandhead has not been observed. Another isomer with a half life of 6.3 s has also been observed with its new decay paths established. Its excitation energy is raised by 79 keV, but its I ^π is not changed.