Search for the inverse fission of uranium

A search for the ``inverse fission'' of uranium has been made. Two ``inverse fission'' reactions were studied, the reaction of $^{124}$Sn + $^{100}$Mo and the reaction of $^{132}$Sn + $^{100}$Mo. In the former case, evaporation residues were searched for using (a) in-beam $\alpha $-spectroscopy, (b) post-irradiation $\alpha $-spectroscopy and (c) in-beam detection of recoiling evaporation residues while in the latter case, the evaporation residue, $^{230}$U was searched for using post irradiation radio-analytical techniques. Data acquisition and analysis is on-going with expected upper limits or production cross sections of $<$ 1 microbarn. The implications of these results for determining the fusion probability, P$_{CN}$, in the collisions of massive nuclei are discussed.