The precise quantification of fusion suppression in heavy-projectile induced reactions is obscured by dominant noncompound processes, limited data, and uncertain models. Mass-total kinetic energy (MTKE) distributions for the reaction ${}^{54}\mathrm{Cr}+{}^{209}\mathrm{Bi}$ were measured at three beam energies, $E_{\mathrm{beam}}=261$, 271, and 278 MeV. The fission fragments were detected using the newly developed TOSCA spectrometer setup. This Letter reveals, for the first time, two asymmetric mass modes at $\sim 80\mathrm{u}$ (complementary $\sim 183\mathrm{u}$), and $\sim 105$ u (complementary $\sim 158\mathrm{u}$), likely associated with the spherical $N=50$ shell and the deformed $Z\approx 42/N\approx 94$ shells, respectively. At the lowest energy, the symmetric mode exhibits a narrow, super-short-like width and high correlated TKE caused likely by $Z=50$, $N=82$ shells. The fusion probability (${\mathrm{P}}_{\mathrm{CN}}$) from multi-Gaussian fits to gated mass (and TKE) distributions using a refined tail-subtraction approach to remove the quasifission background remains robust despite model dependence. $P_{\mathrm{CN}}$ peaks near the barrier and decreases on either side, with a slower decrease at the above-barrier energy, differing from the sub-barrier fusion enhancement reported in [Phys. Rev. Lett. 122, 232503 (2019)] and indicating an open question for further study.

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• Fission
• Nuclear fusion
• Nuclear reactions