Transitions between nuclear states with a large deformation difference may
have large transition probabilities for E0 decay. Such an E0 decay has been
found in the decay of the superdeformed U-238 fission isomer back into the
normal-defonned states [1]. However, a search for the E0 back-decay in U-2
36 showed no result [2]. A setup has been developed to search for conversio
n electrons in this decay.