skip to main content

DOE PAGESDOE PAGES

Title: Collectivity in A ~ 70 nuclei studied via lifetime measurements in 70Br and 68,70Se

Transition strengths for decays from low-lying states in A ~ 70 nuclei have been deduced from lifetime measurements using the recoil distance Doppler shift technique. The results confirm the collectivity previously reported for the 2$$+\atop{1}$$→ 0$$+\atop{gs}$$ decay in 68Se and reveal a relative decrease in collectivity in 70Br. This trend is reproduced by shell model calculations using the GXPF1A interaction in an fp model space including the Coulomb, spin-orbit and isospin non-conserving interactions. The 3$$+\atop{1}$$ → 2$$+\atop{1}$$ decay in 70Br is found to have a very small B(M1) value, which is consistent with the configuration of the state being dominated by the coupling of f 5/2 protons and neutrons. The results suggest that the g 9/2 orbit does not play an important role at low spin in these nuclei. The B(E2) values for the decays of the (T = 1) 2$$+\atop{1}$$ states in 70Br and 70Se are almost identical, suggesting there is no major shape change between the two nuclei at low spin.
Authors:
ORCiD logo [1] ;  [1] ;  [2] ;  [3] ;  [4] ;  [5] ;  [2] ;  [2] ;  [2] ;  [1] ;  [2] ;  [6] ;  [1] ;  [6] ;  [6] ;  [2] ;  [6] ;  [1] ;  [1] ;  [7] more »;  [2] ;  [1] ;  [1] ;  [2] ;  [2] ;  [2] ;  [2] « less
  1. Univ. of York (United Kingdom). Department of Physics
  2. Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy
  3. Kyushu Sangyo University, Fukuoka (Japan). Department of Physics
  4. Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy; Grand Accélérateur National d'Ions Lourds, Bd. Henri Becquerel (France)
  5. Laboratori Nazionali di Legnaro dell'INFN, Legnaro (Padova) (Italy)
  6. Institut für Kernphysik der Universität zu Köln (Germany).
  7. Univ. of Tennessee, Knoxville, TN (United States). Department of Physics and Astronomy
Publication Date:
Grant/Contract Number:
NA0000979; FG02-96ER40983
Type:
Accepted Manuscript
Journal Name:
Physics Letters. Section B
Additional Journal Information:
Journal Volume: 733; Journal Issue: C; Journal ID: ISSN 0370-2693
Publisher:
Elsevier
Research Org:
Nuclear Science and Security Consortium, Berkeley, CA (United States)
Sponsoring Org:
USDOE National Nuclear Security Administration (NNSA)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; Nuclear transition probabilities; Nucleon knockout reactions; Lifetimes
OSTI Identifier:
1454779

Nichols, A. J., Wadsworth, R., Iwasaki, H., Kaneko, K., Lemasson, A., de Angelis, G., Bader, V. M., Baugher, T., Bazin, D., Bentley, M. A., Berryman, J. S., Braunroth, T., Davies, P. J., Dewald, A., Fransen, C., Gade, A., Hackstein, M., Henderson, J., Jenkins, D. G., Miller, D., Morse, C., Paterson, I., Simpson, E. C., Stroberg, S. R., Weisshaar, D., Whitmore, K., and Wimmer, K.. Collectivity in A ~ 70 nuclei studied via lifetime measurements in 70Br and 68,70Se. United States: N. p., Web. doi:10.1016/j.physletb.2014.04.016.
Nichols, A. J., Wadsworth, R., Iwasaki, H., Kaneko, K., Lemasson, A., de Angelis, G., Bader, V. M., Baugher, T., Bazin, D., Bentley, M. A., Berryman, J. S., Braunroth, T., Davies, P. J., Dewald, A., Fransen, C., Gade, A., Hackstein, M., Henderson, J., Jenkins, D. G., Miller, D., Morse, C., Paterson, I., Simpson, E. C., Stroberg, S. R., Weisshaar, D., Whitmore, K., & Wimmer, K.. Collectivity in A ~ 70 nuclei studied via lifetime measurements in 70Br and 68,70Se. United States. doi:10.1016/j.physletb.2014.04.016.
Nichols, A. J., Wadsworth, R., Iwasaki, H., Kaneko, K., Lemasson, A., de Angelis, G., Bader, V. M., Baugher, T., Bazin, D., Bentley, M. A., Berryman, J. S., Braunroth, T., Davies, P. J., Dewald, A., Fransen, C., Gade, A., Hackstein, M., Henderson, J., Jenkins, D. G., Miller, D., Morse, C., Paterson, I., Simpson, E. C., Stroberg, S. R., Weisshaar, D., Whitmore, K., and Wimmer, K.. 2014. "Collectivity in A ~ 70 nuclei studied via lifetime measurements in 70Br and 68,70Se". United States. doi:10.1016/j.physletb.2014.04.016. https://www.osti.gov/servlets/purl/1454779.
@article{osti_1454779,
title = {Collectivity in A ~ 70 nuclei studied via lifetime measurements in 70Br and 68,70Se},
author = {Nichols, A. J. and Wadsworth, R. and Iwasaki, H. and Kaneko, K. and Lemasson, A. and de Angelis, G. and Bader, V. M. and Baugher, T. and Bazin, D. and Bentley, M. A. and Berryman, J. S. and Braunroth, T. and Davies, P. J. and Dewald, A. and Fransen, C. and Gade, A. and Hackstein, M. and Henderson, J. and Jenkins, D. G. and Miller, D. and Morse, C. and Paterson, I. and Simpson, E. C. and Stroberg, S. R. and Weisshaar, D. and Whitmore, K. and Wimmer, K.},
abstractNote = {Transition strengths for decays from low-lying states in A ~ 70 nuclei have been deduced from lifetime measurements using the recoil distance Doppler shift technique. The results confirm the collectivity previously reported for the 2$+\atop{1}$→ 0$+\atop{gs}$ decay in 68Se and reveal a relative decrease in collectivity in 70Br. This trend is reproduced by shell model calculations using the GXPF1A interaction in an fp model space including the Coulomb, spin-orbit and isospin non-conserving interactions. The 3$+\atop{1}$ → 2$+\atop{1}$ decay in 70Br is found to have a very small B(M1) value, which is consistent with the configuration of the state being dominated by the coupling of f5/2 protons and neutrons. The results suggest that the g9/2 orbit does not play an important role at low spin in these nuclei. The B(E2) values for the decays of the (T = 1) 2$+\atop{1}$ states in 70Br and 70Se are almost identical, suggesting there is no major shape change between the two nuclei at low spin.},
doi = {10.1016/j.physletb.2014.04.016},
journal = {Physics Letters. Section B},
number = C,
volume = 733,
place = {United States},
year = {2014},
month = {4}
}