The ^{5}Be nucleus is particle unbound to proton decay; no resonances have been experimentally observed.

2013Ti01 gives ^{5}Be mass defect as 34.10 MeV 12 by improved Kelson-Garvey systematics. Using this value for the ^{5}Be mass defect, the ground state of ^{5}Be would be 4.59 MeV 12 above the ^{3}He+2p threshold.

The 2016 mass table (2017Wa10) gives the estimated mass defect of ^{5}Be as 37.1 MeV 20. Using this value, the ground state of ^{5}Be would be 7.6 MeV 20 above the ^{3}He+2p threshold.

Negative experimental results:}

^{3}He(^{3}He,n)^{5}Be:

1967Ad05: ^{3}He beams from CIT and Stanford accelerators with energies from 18 MeV to 26 MeV collided with ^{3}He in a gas target and the neutron spectrum measured. No structure was observed corresponding to ^{5}Be states. It was concluded that any ^{5}Be states must be at least 4.2 MeV above the ^{3}He+2p threshold.

Theory:}

1981Be10: The author presented a shell model calculation of α=5 nuclei with the goal of testing the t=3/2 IMME for α=5. His calculated binding energy for ^{5}Be is 1.5 MeV. This gives a mass defect of 35.7 MeV and a resonance energy of 6.2 MeV relative to the ^{3}He+2p threshold. There is no mention of the J^{π} value for the state.

2003Ar18: The authors used a three body cluster model with effective interactions that give reasonable results for other nearby nuclei as well as p+^{3}He phase shifts. The authors suspect that the absence of a tensor component in their effective interaction may be of significance. They obtained the following results, where the resonance energies are given relative to the ^{3}He+2p threshold.

Note that the 3/2^{+} and 5/2^{+} states are nearly degenerate and very broad and are not likely to show up in reactions as separate resonances.

The

^{5}Be nucleus is particle unbound to proton decay; no resonances have been experimentally observed.2013Ti01 gives

^{5}Be mass defect as 34.10 MeV12by improved Kelson-Garvey systematics. Using this value for the^{5}Be mass defect, the ground state of^{5}Be would be 4.59 MeV12above the^{3}He+2p threshold.The 2016 mass table (2017Wa10) gives the estimated mass defect of

^{5}Be as 37.1 MeV20. Using this value, the ground state of^{5}Be would be 7.6 MeV20above the^{3}He+2p threshold.Negative experimental results:}^{3}He(^{3}He,n)^{5}Be:1967Ad05:^{3}He beams from CIT and Stanford accelerators with energies from 18 MeV to 26 MeV collided with^{3}He in a gas target and the neutron spectrum measured. No structure was observed corresponding to^{5}Be states. It was concluded that any^{5}Be states must be at least 4.2 MeV above the^{3}He+2p threshold.Theory:}1981Be10: The author presented a shell model calculation of α=5 nuclei with the goal of testing the t=3/2 IMME for α=5. His calculated binding energy for^{5}Be is 1.5 MeV. This gives a mass defect of 35.7 MeV and a resonance energy of 6.2 MeV relative to the^{3}He+2p threshold. There is no mention of the J^{π}value for the state.2003Ar18: The authors used a three body cluster model with effective interactions that give reasonable results for other nearby nuclei as well as p+^{3}He phase shifts. The authors suspect that the absence of a tensor component in their effective interaction may be of significance. They obtained the following results, where the resonance energies are given relative to the^{3}He+2p threshold.Note that the 3/2^{+}and 5/2^{+}states are nearly degenerate and very broad and are not likely to show up in reactions as separate resonances.See other more general theoretical analyses in (1975Be31, 1981Ka39, 1982Ng01, 2004Sa50)