
^{14}Be (1991AJ01)(See the Isobar Diagram for ^{14}Be) ^{14}Be has been observed in the ^{14}C(π^{}, π^{+})^{14}B reaction (1984GI09), in the interaction of 30 MeV/A ^{18}O ions with ^{181}Ta (1986CU01) and in the spallation of thorium by 800 MeV protons (1988WO09). See also (1986AJ01). The atomic mass excess reported by (1984GI09) is 40.10 ± 0.13 MeV but it is not clear that the ground state was observed. (1988WO09) report an atomic mass excess of 39.74 ± 0.14 MeV which we adopt. ^{14}Be is then bound by 3.0 and 1.12 MeV, respectively, with respect to decay into ^{13}Be + n and ^{12}Be + 2n [see, however, ^{13}Be]. ^{14}Be decays by β^{} emission to states in ^{14}B. Its halflife is 4.2 ± 0.7 ms (1986CU01), 4.35 ± 0.17 ms (1988DU09). We adopt the latter value. The branching ratios for 0n, 1n and 2n emission are 0.14 ± 0.03, 0.81 ± 0.04 and 0.05 ± 0.02 (1988DU09). We remind the reader that the two bound states of ^{14}B are the ground state [J^{π} = 2^{}] and an excited state with J^{π} = (1^{}). The binding energies of 1n and 2n in ^{14}B are, respectively, 0.97 and 5.85 MeV: see Fig. 5. The interaction cross section at 790 MeV/A for ^{14}Be ions on C is reported by (1988TA10) who also derive the interaction and the r.m.s. radii for the nucleon distribution in ^{14}Be. See also (1989BE03; theor.) and (1989SA10). A calculation in a (0 + 1)ℏω model space suggests that the first four states of ^{14}Be calculated to be at 0, 1.95, 3.67 and 5.30 MeV have J^{π} = 0^{+}, 2^{+}, 4^{+}, 2^{+}, respectively (1985PO10). See also (1986AN07, 1986WI04, 1987AJ1A, 1988MI1G, 1988TA1N, 1989AJ1A, 1989DE52, 1989TA1K, 1989TA2S, 1989VOZM) and (1987BL18, 1987SA15, 1987YA16, 1989PO1K, 1990BR1S, 1990LO10; theor.).
