Projectile-like fragments (PLF's) emitted in damped collisions of 15 M
eV/u Ne-20 ions with Au-197 were observed in coincidence with two fiss
ion fragments. For given detection angles of the PLF's differential an
d energy-integrated fission probabilities were obtained and the averag
e missing momentum vectors were deduced by using improved analysis met
hods of the fission fragment angular correlation. The average missing
momentum vectors were found to point in the direction of the observed
PLF, with a systematic deviation towards beam direction for larger mas
s transfers. The missing momentum thus appears to mainly originate fro
m the sequential decay of the PLF's.