Superheavy elements are formed in fusion reactions which are hindered by fast nonequilibrium processes. To quantify these, mass-angle distributions and cross sections have been measured, at beam energies from below-barrier to 25% above, for the reactions of 48 Ca, 50 Ti, and 54 Cr with 208 Pb. Moving from 48 Ca to 54 Cr leads to a drastic fall in the symmetric fission yield, which is reflected in the measured massangle distribution by the presence of competing fast nonequilibrium deep inelastic and quasifission processes. These are responsible for reduction of the compound nucleus formation probablity P CN (as measured by the symmetric-peaked fission cross section), by a factor of 2.5 for 50 Ti and 15 for 54 Cr in comparison to 48 Ca. The energy dependence of P CN indicates that cold fusion reactions (involving 208 Pb) are not driven by a diffusion process.

Asim (2019). Extracting the spectral signature of alpha-clustering in 44,48,52Ti using the continuous wavelet transform. Physical Review C -Nuclear Physics, 100 (051302).

An experiment has been carried out using the 9Be(3He, r)9B* reaction at a beam energy of 33 MeV. A large acceptance silicon-strip array was used to detect the 9B* break-up in coincidence with the triton ejectiles in the high-resolution Munich-Q3D spectrograph. The excitation energy regime <3 MeV has been explored and the spectrum resulting from proton decaying states, isolated and characterized. Additional resonance strength is observed at 1.86 MeV ±70 keV(stat) ±35 keV(syst), in agreement with two other recent measurements at higher energies and different angles. The consequences for the "missing" >/2+ first excited state are discussed. Additionally, the branching ratios for the 2.36 MeV 5/i~ state have been measured as r»o/r = 0.98 ± 0.12 and i> /r = 0.016 ± 0.008, in close agreement with earlier work.

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