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Full-Text Articles in Physics
Search For Unbound Be-15 States In The 3n+Be-12 Channel, A. N. Kuchera, A. Spyrou, J. K. Smith, T. Baumann, G. Christian, Paul A. De Young, J. E. Finck, N. Frank, M. D. Jones, Z. Kohley, S. Mosby, W. A. Peters, M. Thoennessen
Search For Unbound Be-15 States In The 3n+Be-12 Channel, A. N. Kuchera, A. Spyrou, J. K. Smith, T. Baumann, G. Christian, Paul A. De Young, J. E. Finck, N. Frank, M. D. Jones, Z. Kohley, S. Mosby, W. A. Peters, M. Thoennessen
Faculty Publications
Background: Be-15 is expected to have low-lying 3/2(+) and 5/2(+) states. A first search did not find the 3/2(+) [A. Spyrou et al., Phys. Rev. C 84, 044309 (2011)]; however, a resonance in Be-15 was populated in a second attempt and determined to be unbound with respect to Be-14 by 1.8(1) MeV with a tentative spin-parity assignment of 5/2(+) [J. Snyder et al., Phys. Rev. C 88, 031303(R) (2013)]. Purpose: Search for the predicted Be-15 3/2(+) state in the three-neutron decay channel. Method: A two-proton removal reaction from a 55 MeV/u C-17 beam was used to populate neutron-unbound states in …
Exploiting Neutron-Rich Radioactive Ion Beams To Constrain The Symmetry Energy, Z. Kohley, G. Christian, T. Baumann, Paul A. Deyoung, J. E. Finck, N. Frank, M. Jones, J. K. Smith, J. Snyder, A. Spyrou, M. Thoennessen
Exploiting Neutron-Rich Radioactive Ion Beams To Constrain The Symmetry Energy, Z. Kohley, G. Christian, T. Baumann, Paul A. Deyoung, J. E. Finck, N. Frank, M. Jones, J. K. Smith, J. Snyder, A. Spyrou, M. Thoennessen
Faculty Publications
The Modular Neutron Array (MoNA) and 4 Tm Sweeper magnet were used to measure the free neutrons and heavy charged particles from the radioactive ion beam induced Mg-32 + Be-9 reaction. The fragmentation reaction was simulated with the constrained molecular dynamics model (CoMD), which demonstrated that the < N/Z > of the heavy fragments and free neutron multiplicities were observables sensitive to the density dependence of the symmetry energy at subsaturation densities. Through comparison of these simulations with the experimental data, constraints on the density dependence of the symmetry energy were extracted. The advantage of radioactive ion beams as a probe of the …
First Observation Of Be-15, J. Snyder, T. Baumann, G. Christian, R. A. Haring-Kaye, Paul A. Deyoung, Z. Kohley, B. Luther, M. Mosby, A. Simon, J. K. Smith, A. Spyrou, S. Stephenson, M. Thoennessen
First Observation Of Be-15, J. Snyder, T. Baumann, G. Christian, R. A. Haring-Kaye, Paul A. Deyoung, Z. Kohley, B. Luther, M. Mosby, A. Simon, J. K. Smith, A. Spyrou, S. Stephenson, M. Thoennessen
Faculty Publications
The neutron-unbound nucleus Be-15 was observed for the first time. It was populated using neutron transfer from a deuterated polyethylene target with a 59 MeV/u Be-14 beam. Neutrons were measured in coincidence with outgoing Be-14 particles and the reconstructed decay energy spectrum exhibits a resonance at 1.8(1) MeV. This corresponds to Be-15 being unbound by 0.45 MeV more then Be-16 thus significantly hindering the sequential two-neutron decay of Be-16 to Be-14 through this state.