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Search for excited states in O 25

Journal Article · · Physical Review. C
 [1];  [2];  [2];  [3];  [4];  [5];  [6];  [2];  [2];  [2];  [7];  [8];  [2];  [2];  [2]
  1. Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); DOE/OSTI
  2. Michigan State University, East Lansing, MI (United States)
  3. Hope College, Holland, MI (United States)
  4. Central Michigan University, Mount Pleasant, MI (United States)
  5. Augustana College, Rock Island, IL (United States)
  6. Davidson College, NC (United States)
  7. Reed College, Portland, OR (United States)
  8. Gettysburg College, PA (United States)
+ Show Author Affiliations
Theoretical calculations suggest the presence of low-lying excited states in 25O. Previous experimental searches by means of proton knockout on 26F produced no evidence for such excitations. We search for excited states in 25O using the 24O(d,p)25O reaction. The theoretical analysis of excited states in unbound 25,27O is based on the configuration interaction approach that accounts for couplings to the scattering continuum. We use invariant-mass spectroscopy to measure neutron-unbound states in 25O. For the theoretical approach, we use the complex-energy Gamow Shell Model and Density Matrix Renormalization Group method with a finite-range two-body interaction optimized to the bound states and resonances of 23–26O, assuming a core of 22O. Here we predict energies, decay widths, and asymptotic normalization coefficients. Our calculations in a large spdf space predict several low-lying excited states in 25O of positive and negative parity, and we obtain an experimental limit on the relative cross section of a possible Jπ = 1/2+ state with respect to the ground state of 25O at σ1/2+/σg.s. = 0.25$$^{+1.0}_{-0.25}$$. We also discuss how the observation of negative parity states in 25O could guide the search for the low-lying negative parity states in 27O. Previous experiments based on the proton knockout of 26F suffered from the low cross sections for the population of excited states in 25O because of low spectroscopic factors. In this respect, neutron transfer reactions carry more promise.
Research Organization:
Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Michigan State University, East Lansing, MI (United States)
Sponsoring Organization:
National Science Foundation (NSF); USDOE; USDOE National Nuclear Security Administration (NNSA); USDOE Office of Science (SC), Nuclear Physics (NP)
Grant/Contract Number:
AC02-05CH11231; NA0003180; SC0008511; SC0013365
OSTI ID:
1541007
Alternate ID(s):
OSTI ID: 1409876
Journal Information:
Physical Review. C, Journal Name: Physical Review. C Journal Issue: 5 Vol. 96; ISSN 2469-9985
Publisher:
American Physical Society (APS)Copyright Statement
Country of Publication:
United States
Language:
English

References (44)

Are There Good Probes for the Di-Neutron Correlation in Light Neutron-Rich Nuclei? journal October 2015
On the use of resonant states in eigenfunction expansions of scattering and reaction amplitudes journal February 1968
Completeness relations, Mittag-Leffler expansions and the perturbation theory of resonant states journal November 1982
MoNA—The Modular Neutron Array
  • Luther, B.; Baumann, T.; Thoennessen, M.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 505, Issue 1-2 https://doi.org/10.1016/S0168-9002(03)01014-3
journal June 2003
Geant4—a simulation toolkit
  • Agostinelli, S.; Allison, J.; Amako, K.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 506, Issue 3 https://doi.org/10.1016/S0168-9002(03)01368-8
journal July 2003
Pairing-induced localization of the particle continuum in weakly bound nuclei journal October 2000
COSY INFINITY Version 9
  • Makino, Kyoko; Berz, Martin
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 558, Issue 1 https://doi.org/10.1016/j.nima.2005.11.109
journal March 2006
Reconstruction of nuclear charged fragment trajectories from a large-gap sweeper magnet
  • Frank, N.; Schiller, A.; Bazin, D.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 580, Issue 3 https://doi.org/10.1016/j.nima.2007.07.008
journal October 2007
Resonance and continuum Gamow shell model with realistic nuclear forces journal June 2017
Shell structure of exotic nuclei journal July 2007
Living on the edge of stability, the limits of the nuclear landscape journal January 2013
Emergent properties of nuclei from ab initio coupled-cluster calculations journal May 2016
Shell model in the complex energy plane journal October 2008
Low-lying continuum states of drip-line oxygen isotopes journal September 2015
Relation between pairing correlations and two-particle space correlations journal March 1984
Particle stability of the isotopes O 26 and Ne 32 in the reaction 44 MeV/nucleon Ca 48 +Ta journal March 1990
Mean-field description of ground-state properties of drip-line nuclei: Pairing and continuum effects journal June 1996
Giant halo at the neutron drip line in Ca isotopes in relativistic continuum Hartree-Bogoliubov theory journal March 2002
Generic strong coupling behavior of Cooper pairs on the surface of superfluid nuclei journal August 2007
New efficient method for performing Hartree-Fock-Bogoliubov calculations for weakly bound nuclei journal May 2008
Density matrix renormalization group approach to two-fluid open many-fermion systems journal January 2009
Gamow shell-model calculations of drip-line oxygen isotopes journal November 2009
Nuclear energy density optimization journal August 2010
Persistent contribution of unbound quasiparticles to the pair correlation in the continuum Skyrme-Hartree-Fock-Bogoliubov approach journal May 2011
Spectroscopy of neutron-unbound 27 , 28 F journal March 2012
Asymptotic normalization coefficients and continuum coupling in mirror nuclei journal June 2012
First observation of 15 Be journal September 2013
Beyond the neutron drip line: The unbound oxygen isotopes 25 O and 26 O journal September 2013
Correlated two-neutron emission in the decay of the unbound nucleus 26O journal January 2014
Two-neutron sequential decay of O 24 journal November 2015
Decay dynamics of the unbound O 25 and O 26 nuclei journal March 2016
Continuum effects in neutron-drip-line oxygen isotopes journal August 2017
Determination of the N = 16 Shell Closure at the Oxygen Drip Line journal April 2008
Evidence for the Ground-State Resonance of O 26 journal April 2012
Continuum Effects and Three-Nucleon Forces in Neutron-Rich Oxygen Isotopes journal June 2012
Study of Two-Neutron Radioactivity in the Decay of O 26 journal April 2013
Nucleus O 26 : A Barely Unbound System beyond the Drip Line journal March 2016
Density matrix formulation for quantum renormalization groups journal November 1992
Density Matrix Renormalization Group Approach for Many-Body Open Quantum Systems journal September 2006
System Testing and Installation of the NHMFL/NSCL Sweeper Magnet journal June 2005
Continuum shell model and nuclear physics at the edge of stability journal August 2014
The oxygen isotopes journal January 2017
Structure of the Second 0+ State of 4He journal July 1978
Cluster-Model Study of the T=1 States in A=4 System: 3He+p Scattering journal October 1979

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS
nuclear reactions
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shell model
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