AUTHOR=Vukman Nikola , Soić Neven , Freer Martin , Alcorta Martin , Connolly Devin , Čolović Petra , Davinson Thomas , Di Pietro Alessia , Lennarz Annika , Psaltis Athanasios , Ruiz Chris , Uroić Milivoj , Williams Matthew TITLE=Cluster decays of 12Be excited states JOURNAL=Frontiers in Physics VOLUME=Volume 10 - 2022 YEAR=2022 URL=https://www.frontiersin.org/journals/physics/articles/10.3389/fphy.2022.1009421 DOI=10.3389/fphy.2022.1009421 ISSN=2296-424X ABSTRACT=An experimental study of the helium-cluster decays of the $^{12}$Be excited states has been performed using the $^{9}$Li + $^{7}$Li $\longrightarrow$ $\alpha$ + $\alpha$ + $^{8}$He and $^{9}$Li + $^{7}$Li $\longrightarrow$ $\alpha$ + $^{6}$He + $^{6}$He reactions at the $^{9}$Li beam energy of 74.8 MeV. At excitation energies between 10 to 25 MeV, the $^{12}$Be excited states decaying into the $^{4}$He + $^{8}$He, $^{6}$He + $^{6}$He and $^{6}$He + $^{6}$He*(1.8 MeV, J$^{\pi}$ = 2$^{+}$) have been observed. Most of the observed states decaying into the $^{4}$He + $^{8}$He and $^{6}$He + $^{6}$He correspond to previously reported states. The decay to the $^{6}$He + $^{6}$He*(1.8 MeV, J$^{\pi}$ = 2$^{+}$) channel has been observed for the first time. Two of the five states observed in this new decay channel are also observed in the ground state channel $^{6}$He + $^{6}$He, while two may correspond to the $^{4}$He + $^{8}$He decaying states. The states around 13.5 and 20.0 MeV decay to the $^{6}$He + $^{6}$He and $^{4}$He + $^{8}$He channels, while the state around 22.3 MeV decays into all three decay channels examined. This experiment is complementary to all previous studies of the $^{12}$Be cluster states because of the different reaction mechanism employed for the population of the $^{12}$Be cluster states. The observation of the states at high excitations with these exotic decay properties is strongly supporting the molecular structure of the $^{12}$Be excited states.