Fission of 180Hg and 264Fm: a comparative study

180Hg is experimentally found to fission asymmetrically. This result was not expected as a naive fragment shell effects study would support the symmetric mode to be the most probable. In the present study we investigate both symmetric and asymmetric 180Hg fission modes at the mean field level using various multipole moment constraints. Potential energy surfaces are analysed in terms of shell effects that shape their topographies and connections to fragment shell effects are made. The non-occurrence of low energy symmetric fission is interpreted in terms of 90Zr fragment properties. Throughout this study a comparison with 264Fm and its symmetric doubly magic 132Sn fission fragments is done.