M. Warren

Publications (3)7.37 Total impact

• Article: Spectroscopy of neutron-unbound $^{27,28}$F

  G. Christian, N. Frank, S. Ash, T. Baumann, P. A. DeYoung, J. E. Finck, A. Gade, G. F. Grinyer, B. Luther, M. Mosby, S. Mosby, J. K. Smith, J. Snyder, A. Spyrou, M. J. Strongman, M. Thoennessen, M. Warren, D. Weisshaar, A. Wersal
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  ABSTRACT: The ground state of $^{28}$F has been observed as an unbound resonance $2\underline{2}0$ keV above the ground state of $^{27}$F. Comparison of this result with USDA/USDB shell model predictions leads to the conclusion that the $^{28}$F ground state is primarily dominated by $sd$-shell configurations. Here we present a detailed report on the experiment in which the ground state resonance of $^{28}$F was first observed. Additionally, we report the first observation of a neutron-unbound excited state in $^{27}$F at an excitation energy of $25\underline{0}0 (2\underline{2}0)$ keV.
  03/2012;
• Source

  Available from: N. Frank

  Article: Exploring the Low-$Z$ Shore of the Island of Inversion at $N = 19$

  G. Christian, N. Frank, S. Ash, T. Baumann, D. Bazin, J Brown, P. A. DeYoung, J. E. Finck, A Gade, G. F. Grinyer, [......], G. F. Peaslee, W. F. Rogers, J. K. Smith, J. Snyder, A. Spyrou, M. J. Strongman, M. Thoennessen, M. Warren, D. Weisshaar, A. Wersal
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  ABSTRACT: The technique of invariant mass spectroscopy has been used to measure, for the first time, the ground state energy of neutron-unbound $^{28}\textrm{F},$ determined to be a resonance in the $^{27}\textrm{F} + n$ continuum at $2\underline{2}0 (\underline{5}0)$ keV. States in $^{28}\textrm{F}$ were populated by the reactions of a 62 MeV/u $^{29}\textrm{Ne}$ beam impinging on a 288 $\textrm{mg/cm}^2$ beryllium target. The measured $^{28}\textrm{F}$ ground state energy is in good agreement with USDA/USDB shell model predictions, indicating that $pf$ shell intruder configurations play only a small role in the ground state structure of $^{28}\textrm{F}$ and establishing a low-$Z$ boundary of the island of inversion for N=19 isotones.
  Physical Review Letters 01/2012; 108(3). · 7.37 Impact Factor
• Article: Spectroscopy of neutron-unbound $^27,28mathrmF$

  Christian, N Frank, S Ash, T Baumann, P A DeYoung, J E Finck, A Gade, G F Grinyer, B Luther, M Mosby, S Mosby, J K Smith, J Snyder, A Spyrou, M J Strongman, M Thoennessen, M Warren, D Weisshaar, A Wersal
  Phys. Rev. C. 01/2012; 85(3):034327.