Unresolved Question of the He-10 Ground State Resonance
The ground state of He-10 was populated using a 2p2n-removal reaction from a 59 MeV/u Be-14 beam. The decay energy of the three-body system, He-8 + n + n, was measured and a resonance was observed at E = 1.60(25) MeV with a 1.8(4) MeV width. This result is in agreement with previous invariant mass spectroscopy measurements, using the Li-11(-p) reaction, but is inconsistent with recent transfer reaction results. The proposed explanation that the difference, about 500 keV, is due to the effect of the extended halo nature of Li-11 in the one-proton knockout reaction is no longer valid as the present work demonstrates that the discrepancy between the transfer reaction results persists despite using a very different reaction mechanism, Be-14(-2p2n). DOI: 10.1103/PhysRevLett.109.232501
Kohley, Z., J. Snyder, T. Baumann, G. Christian, Paul A. DeYoung, J. E. Finck, R. A. Haring-Kaye, M. Jones, E. Lunderberg, B. Luther, S. Mosby, A. Simon, J. K. Smith, A. Spyrou, S. L. Stephenson and M. Thoennessen. "Unresolved Question of the He-10 Ground State Resonance." Physical Review Letters 109, no. 23 (2012): 232501-1-232501-5.