Dipole bands in nucleus 139Pm

High-spin states in nucleus ¹³⁹Pm have been studied using the reaction ¹¹⁶Cd(²⁷Al, 4n)¹³⁹Pm. Two dipole cascades have been found. Spin and parity assignments were based on the Directional Correlation of Oriented Nuclei (DCO) ratios and systematic behavior in neighboring odd-proton nuclei. The level structures of ¹³⁹Pm are compared with those of the N = 78 isotone ¹⁴¹Eu in which two dipole bands have been confirmed as magnetic rotational bands. The close similarity between them suggests that the dipole bands in ¹³⁹Pm may be magnetic rotational bands.