Unresolved Question of the $^{10}\mathrm{He}$ Ground State Resonance

Unresolved Question of the ${}^{10}{He}$ Ground State Resonance

Z. Kohley, J. Snyder, T. Baumann, G. Christian, P. 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

Phys. Rev. Lett. 109, 232501 – Published 4 December 2012

Abstract

The ground state of ${}^{10}{He}$ was populated using a $2 p 2 n$ -removal reaction from a $59 MeV / u$ ${}^{14}{Be}$ beam. The decay energy of the three-body system, ${}^{8}{He} + n + n$ , 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 ${}^{11}{Li} (- p)$ 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about 500 keV, is due to the effect of the extended halo nature of ${}^{11}{Li}$ in the one-proton knockout reaction is no longer valid as the present work demonstrates that the discrepancy between the transfer reaction results persists despite using a very different reaction mechanism, ${}^{14}{Be} (- 2 p 2 n)$ .

Received 8 August 2012

DOI:https://doi.org/10.1103/PhysRevLett.109.232501

Authors & Affiliations

Z. Kohley^1,*, J. Snyder^1,2, T. Baumann³, G. Christian^1,2,†, P. A. DeYoung⁴, J. E. Finck⁵, R. A. Haring-Kaye⁶, M. Jones^1,2, E. Lunderberg⁴, B. Luther⁷, S. Mosby^1,2,‡, A. Simon¹, J. K. Smith^1,2, A. Spyrou^1,2, S. L. Stephenson⁸, and M. Thoennessen^1,2

¹National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
²Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
³National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
⁴Department of Physics, Hope College, Holland, Michigan 49422-9000, USA
⁵Department of Physics, Central Michigan University, Mount Pleasant, Michigan 48859, USA
⁶Department of Physics and Astronomy, Ohio Wesleyan University, Delaware, Ohio 43015, USA
⁷Department of Physics, Concordia College, Moorhead, Minnesota 56562, USA
⁸Department of Physics, Gettysburg College, Gettysburg, Pennsylvania 17325, USA

^*zkohley@gmail.com
^†Present address: TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia V6T 2A3, Canada.
^‡Present address: Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.