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Title: Is the Structure of Si 42 Understood?

Abstract

A more detailed test of the implementation of nuclear forces that drive shell evolution in the pivotal nucleus 42Si—going beyond earlier comparisons of excited-state energies—is important. The two leading shell-model effective interactions, SDPF-MU and SDPF-U-Si, both of which reproduce the low-lying 42Si(2+1) energy, but whose predictions for other observables differ significantly, are interrogated by the population of states in neutron-rich 42Si with a one-proton removal reaction from 43P projectiles at 81 MeV/nucleon. The measured cross sections to the individual 42Si final states are compared to calculations that combine eikonal reaction dynamics with these shell-model nuclear structure overlaps. The differences in the two shell-model descriptions are examined and linked to predicted low-lying excited 0 + states and shape coexistence. Based on the present data, which are in better agreement with the SDPF-MU calculations, the state observed at 2150(13) keV in 42Si is proposed to be the second 0$$ ^+ _2 $$ level.

Authors:
 [1];  [1];  [2];  [1];  [1];  [3];  [3];  [1];  [4];  [1];  [1];  [1];  [1]
  1. Michigan State Univ., East Lansing, MI (United States)
  2. Univ. of Surrey, Guildford (United Kingdom)
  3. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
  4. Florida State Univ., Tallahassee, FL (United States)
Publication Date:
Research Org.:
Michigan State Univ., East Lansing, MI (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA)
OSTI Identifier:
1524453
Alternate Identifier(s):
OSTI ID: 1524470; OSTI ID: 1580880
Grant/Contract Number:  
FG02-08ER41556; NA0003180; SC0014537; AC02-05CH11231
Resource Type:
Accepted Manuscript
Journal Name:
Physical Review Letters
Additional Journal Information:
Journal Volume: 122; Journal Issue: 22; Journal ID: ISSN 0031-9007
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS

Citation Formats

Gade, A., Brown, B. A., Tostevin, J. A., Bazin, D., Bender, P. C., Campbell, C. M., Crawford, H. L., Elman, B., Kemper, K. W., Longfellow, B., Lunderberg, E., Rhodes, D., and Weisshaar, D. Is the Structure of Si42 Understood?. United States: N. p., 2019. Web. doi:10.1103/PhysRevLett.122.222501.
Gade, A., Brown, B. A., Tostevin, J. A., Bazin, D., Bender, P. C., Campbell, C. M., Crawford, H. L., Elman, B., Kemper, K. W., Longfellow, B., Lunderberg, E., Rhodes, D., & Weisshaar, D. Is the Structure of Si42 Understood?. United States. doi:10.1103/PhysRevLett.122.222501.
Gade, A., Brown, B. A., Tostevin, J. A., Bazin, D., Bender, P. C., Campbell, C. M., Crawford, H. L., Elman, B., Kemper, K. W., Longfellow, B., Lunderberg, E., Rhodes, D., and Weisshaar, D. Tue . "Is the Structure of Si42 Understood?". United States. doi:10.1103/PhysRevLett.122.222501.
@article{osti_1524453,
title = {Is the Structure of Si42 Understood?},
author = {Gade, A. and Brown, B. A. and Tostevin, J. A. and Bazin, D. and Bender, P. C. and Campbell, C. M. and Crawford, H. L. and Elman, B. and Kemper, K. W. and Longfellow, B. and Lunderberg, E. and Rhodes, D. and Weisshaar, D.},
abstractNote = {A more detailed test of the implementation of nuclear forces that drive shell evolution in the pivotal nucleus 42Si—going beyond earlier comparisons of excited-state energies—is important. The two leading shell-model effective interactions, SDPF-MU and SDPF-U-Si, both of which reproduce the low-lying 42Si(2+1) energy, but whose predictions for other observables differ significantly, are interrogated by the population of states in neutron-rich 42Si with a one-proton removal reaction from 43P projectiles at 81 MeV/nucleon. The measured cross sections to the individual 42Si final states are compared to calculations that combine eikonal reaction dynamics with these shell-model nuclear structure overlaps. The differences in the two shell-model descriptions are examined and linked to predicted low-lying excited 0+ states and shape coexistence. Based on the present data, which are in better agreement with the SDPF-MU calculations, the state observed at 2150(13) keV in 42Si is proposed to be the second 0$ ^+ _2 $ level.},
doi = {10.1103/PhysRevLett.122.222501},
journal = {Physical Review Letters},
number = 22,
volume = 122,
place = {United States},
year = {2019},
month = {6}
}

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