alpha : 2n : alpha Molecular Band in Be-10

Abstract

The 10.15 MeV resonance in $^{10}$Be has been probed via resonant $^{6}$He+$^{4}$He elastic scattering. It is demonstrated that it is the J$^{p}$i=4$^{+}$ member of a rotational band built on the 6.18 MeV 0$^{+ }$state. A Gammaalpha of 0.10–0.13 MeV and Gammaalpha/Gamma=0.35–0.46 were deduced. The corresponding reduced alpha width, gammaalpha2, indicates one of the largest alpha-cluster spectroscopic factors known. The deformation of the band, including the 7.54 MeV, 2$^{+}$ member, is large ([h-bar]2/2I=200 keV). Such a deformation and the significant degree of clusterization signals a well-developed alpha:2n:alpha molecular structure