Search for fusion suppression in reactions having entrance-channel mass-asymmetry values around the Businaro-Gallone point

Available data on evaporation residue (ER) production and fission in a wide region of compound nucleus (CN) masses and entrance‐channel mass‐asymmetry values have been analyzed in search for the “starting point”, where the fusion suppression due to the quasi‐fission (QF) effect starts to show up. Comparing cross sections for the ER production and fission in reactions leading to the same CN, but having different values of entrance‐channel mass‐asymmetry, one can extract the fusion probability for a more symmetric combination with respect to quite an asymmetric one, where no limitation seems to occur. An attempt to find correlations between the fusion probabilities derived for the considered combinations and some entrance‐channel characteristics is undertaken