Strongly deformed nuclear shapes at ultra-high spin and shape coexistence in N ~ 90 nuclei

Riley, M. A.; Aguilar, A.; Evans, A. O.; Hartley, D. J.; Lagergren, K.; Ollier, J.; Paul, E. S.; Pipidis, A.; Simpson, J.; Teal, C.; Twin, P. J.; Wang, X.; Appelbe, D. E.; Campbell, D. B.; Carpenter, M. P.; Clark, R. M.; Cromaz, M.; Darby, I. G.; Fallon, P.; Garg, U; Janssens, R. V. F.; Joss, D. T.; Kondev, F. G.; Lauritsen, T.; Lee, I. Y.; Lister, C. J.; Macchiavelli, A. O.; Nolan, P. J.; Petri, M.; Rigby, S. V.; Thompson, J.; Unsworth, C.; Ward, D.; Zhu, S.; Ragnarsson, I.

Title: Strongly deformed nuclear shapes at ultra-high spin and shape coexistence in N ~ 90 nuclei

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Abstract

The N ~ 90 region of the nuclear chart has featured prominently as the spectroscopy of nuclei at extreme spin has progressed. This talk will present recent discoveries from investigations of high spin behavior in the N ~ 90 Er, Tm and Yb nuclei utilizing the Gammasphere gamma-ray spectrometer. In particular it will include discussion of the beautiful shape evolution and coexistence observed in these nuclei along with the identification of a remarkable new family of band structures. The latter are very weakly populated rotational sequences with high moment of inertia that bypass the classic terminating configurations near spin 40-50h, marking a return to collectivity that extends discrete γ-ray spectroscopy to well over 60h. Establishing the nature of the yrast states in these nuclei beyond the oblate band-termination states has been a major goal for the past two decades. Cranking calculations suggest that these new structures most likely represent stable triaxial strongly deformed bands that lie in a valley of favored shell energy in deformation and particle-number space.

Authors:

Riley, M. A. ^[1]; Aguilar, A. ^[1]; Evans, A. O. ^[2]; Hartley, D. J. ^[3]; Lagergren, K. ^[1]; Ollier, J. ^[4]; Paul, E. S. ^[2]; Pipidis, A. ^[1]; Simpson, J. ^[4]; Teal, C. ^[1]; Twin, P. J. ^[2]; Wang, X. ^[1]; Appelbe, D. E. ^[4]; Campbell, D. B. ^[1]; Carpenter, M. P. ^[5]; Clark, R. M. ^[6]; Cromaz, M. ^[6]; Darby, I. G. ^[7]; Fallon, P. ^[6]; Garg, U ^[8] more »

Florida State Univ., Tallahassee, FL (United States)
Univ. of Liverpool, Liverpool (United Kingdom)
U.S. Naval Academy, Annapolis, MD (United States)
STFC Daresbury Lab., Warrington (United Kingdom)
Argonne National Lab. (ANL), Argonne, IL (United States)
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Univ. of Tennessee, Knoxville, TN (United States)
Univ. of Notre Dame, Notre Dame, IN (United States)
Lund Univ., Lund (Sweden)

Publication Date:: Thu Jan 01 00:00:00 EST 2009

Research Org.:: Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

Sponsoring Org.:: USDOE Office of Science (SC)

OSTI Identifier:: 1407071

Grant/Contract Number:: AC02-05CH11231

Resource Type:: Accepted Manuscript

Journal Name:: Acta Physica Polonica. Series B

Additional Journal Information:: Journal Volume: 40; Journal Issue: 3; Conference: Zakopane Conference on Nuclear Physics, Zakopane (Poland), 1-7 Sep 2008; Journal ID: ISSN 0587-4254

Publisher:: Jagiellonian University

Country of Publication:: United States

Language:: English

Subject:: 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; 73 NUCLEAR PHYSICS AND RADIATION PHYSICS

Citation Formats


                    Riley, M. A., Aguilar, A., Evans, A. O., Hartley, D. J., Lagergren, K., Ollier, J., Paul, E. S., Pipidis, A., Simpson, J., Teal, C., Twin, P. J., Wang, X., Appelbe, D. E., Campbell, D. B., Carpenter, M. P., Clark, R. M., Cromaz, M., Darby, I. G., Fallon, P., Garg, U, Janssens, R. V. F., Joss, D. T., Kondev, F. G., Lauritsen, T., Lee, I. Y., Lister, C. J., Macchiavelli, A. O., Nolan, P. J., Petri, M., Rigby, S. V., Thompson, J., Unsworth, C., Ward, D., Zhu, S., and Ragnarsson, I. Strongly deformed nuclear shapes at ultra-high spin and shape coexistence in N ~ 90 nuclei.  United States: N. p., 2009. 
Web.

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                    Riley, M. A., Aguilar, A., Evans, A. O., Hartley, D. J., Lagergren, K., Ollier, J., Paul, E. S., Pipidis, A., Simpson, J., Teal, C., Twin, P. J., Wang, X., Appelbe, D. E., Campbell, D. B., Carpenter, M. P., Clark, R. M., Cromaz, M., Darby, I. G., Fallon, P., Garg, U, Janssens, R. V. F., Joss, D. T., Kondev, F. G., Lauritsen, T., Lee, I. Y., Lister, C. J., Macchiavelli, A. O., Nolan, P. J., Petri, M., Rigby, S. V., Thompson, J., Unsworth, C., Ward, D., Zhu, S., & Ragnarsson, I. Strongly deformed nuclear shapes at ultra-high spin and shape coexistence in N ~ 90 nuclei.  United States.

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                    Riley, M. A., Aguilar, A., Evans, A. O., Hartley, D. J., Lagergren, K., Ollier, J., Paul, E. S., Pipidis, A., Simpson, J., Teal, C., Twin, P. J., Wang, X., Appelbe, D. E., Campbell, D. B., Carpenter, M. P., Clark, R. M., Cromaz, M., Darby, I. G., Fallon, P., Garg, U, Janssens, R. V. F., Joss, D. T., Kondev, F. G., Lauritsen, T., Lee, I. Y., Lister, C. J., Macchiavelli, A. O., Nolan, P. J., Petri, M., Rigby, S. V., Thompson, J., Unsworth, C., Ward, D., Zhu, S., and Ragnarsson, I. Thu .  
"Strongly deformed nuclear shapes at ultra-high spin and shape coexistence in N ~ 90 nuclei".  United States.  https://www.osti.gov/servlets/purl/1407071.

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@article{osti_1407071,

  title        = {Strongly deformed nuclear shapes at ultra-high spin and shape coexistence in N ~ 90 nuclei},

  author       = {Riley, M. A. and Aguilar, A. and Evans, A. O. and Hartley, D. J. and Lagergren, K. and Ollier, J. and Paul, E. S. and Pipidis, A. and Simpson, J. and Teal, C. and Twin, P. J. and Wang, X. and Appelbe, D. E. and Campbell, D. B. and Carpenter, M. P. and Clark, R. M. and Cromaz, M. and Darby, I. G. and Fallon, P. and Garg, U and Janssens, R. V. F. and Joss, D. T. and Kondev, F. G. and Lauritsen, T. and Lee, I. Y. and Lister, C. J. and Macchiavelli, A. O. and Nolan, P. J. and Petri, M. and Rigby, S. V. and Thompson, J. and Unsworth, C. and Ward, D. and Zhu, S. and Ragnarsson, I.},

  abstractNote = {The N ~ 90 region of the nuclear chart has featured prominently as the spectroscopy of nuclei at extreme spin has progressed. This talk will present recent discoveries from investigations of high spin behavior in the N ~ 90 Er, Tm and Yb nuclei utilizing the Gammasphere gamma-ray spectrometer. In particular it will include discussion of the beautiful shape evolution and coexistence observed in these nuclei along with the identification of a remarkable new family of band structures. The latter are very weakly populated rotational sequences with high moment of inertia that bypass the classic terminating configurations near spin 40-50h, marking a return to collectivity that extends discrete γ-ray spectroscopy to well over 60h. Establishing the nature of the yrast states in these nuclei beyond the oblate band-termination states has been a major goal for the past two decades. Cranking calculations suggest that these new structures most likely represent stable triaxial strongly deformed bands that lie in a valley of favored shell energy in deformation and particle-number space.},

  doi          = {},

  journal      = {Acta Physica Polonica. Series B},

  number       = 3,

  volume       = 40,

  place        = {United States},

  year         = {Thu Jan 01 00:00:00 EST 2009},

  month        = {Thu Jan 01 00:00:00 EST 2009}

}

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