We review proposed production mechanisms of Ta-180 during the nucleosynthes
is process. In this nucleus, an electromagnetic coupling between the ground
state and the 9(-) isomeric state may strongly affect the produced abundan
ces. Possible theoretical electromagnetic paths between the ground state an
d the isomeric state are discussed in the framework of the two-quasiparticl
e-plus-phonon model and the standard axially-symmetric rotor model includin
g Coriolis mixing.