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Title: Isomer-delayed gamma-ray spectroscopy of neutron-rich 166Tb

Abstract

Here, this short paper presents the identification of a metastable, isomeric-state decay in the neutron-rich odd-odd, prolate-deformed nucleus 166Tb. The nucleus of interest was formed using the in-flight fission of a 345 MeV per nucleon 238U primary beam at the RIBF facility, RIKEN, Japan. Gamma-ray transitions decaying from the observed isomeric states in 166Tb were identified using the EURICA gamma-ray spectrometer, positioned at the final focus of the BigRIPS fragments separator. The current work identifies a single discrete gamma-ray transition of energy 119 keV which de-excites an isomeric state in 166Tb with a measured half-life of 3.5(4) μs. The multipolarity assignment for this transition is an electric dipole and is made on the basis internal conversion and decay lifetime arguments. Possible two quasi-particle Nilsson configurations for the initial and final states which are linked by this transition in 166Tb are made on the basis of comparison with Blocked BCS Nilsson calculations, with the predicted ground state configuration for this nucleus arising from the coupling of the v(1-/2)[521] and π(3+/2) Nilsson orbitals.

Authors:
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Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Nuclear Physics (NP) (SC-26)
OSTI Identifier:
1393944
Grant/Contract Number:
AC02-06CH11357
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
EPJ Web of Conferences
Additional Journal Information:
Journal Volume: 146; Journal Issue: 10009; Journal ID: ISSN 2100-014X
Publisher:
EDP Sciences
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS

Citation Formats

Gurgi, L. A., Regan, P. H., Söderström, P. -A., Watanabe, H., Walker, P. M., Podolyák, Zs., Nishimura, S., Berry, T. A., Doornenbal, P., Lorusso, G., Isobe, T., Baba, H., Xu, Z. Y., Sakurai, H., Sumikama, T., Catford, W. N., Bruce, A. M., Browne, F., Lane, G. J., Kondev, F. G., Odahara, A., Wu, J., Liu, H. L., Xu, F. R., Korkulu, Z., Lee, P., Liu, J. J., Phong, V. H., Yagi, A., Zhang, G. X., Alharbi, T., Carroll, R. J., Chae, K. Y., Dombradi, Zs., Estrade, A., Fukuda, N., Griffin, C., Ideguchi, E., Inabe, N., Kanaoka, H., Kojouharov, I., Kubo, T., Kubono, S., Kurz, N., Kuti, I., Lalkovski, S., Lee, E. J., Lee, C. S., Lotay, G., Moon, C. B., Nishizuka, I., Nita, C. R., Patel, Z., Roberts, O. J., Schaffner, H., Shand, C. M., Suzuki, H., Takeda, H., Terashima, S., Vajta, Zs., Kanaya, S., Valiente-Dobòn, J. J., Plompen, A., Hambsch, F. -J., Schillebeeckx, P., Mondelaers, W., Heyse, J., Kopecky, S., Siegler, P., and Oberstedt, S. Isomer-delayed gamma-ray spectroscopy of neutron-rich 166Tb. United States: N. p., 2017. Web. doi:10.1051/epjconf/201714610009.
Gurgi, L. A., Regan, P. H., Söderström, P. -A., Watanabe, H., Walker, P. M., Podolyák, Zs., Nishimura, S., Berry, T. A., Doornenbal, P., Lorusso, G., Isobe, T., Baba, H., Xu, Z. Y., Sakurai, H., Sumikama, T., Catford, W. N., Bruce, A. M., Browne, F., Lane, G. J., Kondev, F. G., Odahara, A., Wu, J., Liu, H. L., Xu, F. R., Korkulu, Z., Lee, P., Liu, J. J., Phong, V. H., Yagi, A., Zhang, G. X., Alharbi, T., Carroll, R. J., Chae, K. Y., Dombradi, Zs., Estrade, A., Fukuda, N., Griffin, C., Ideguchi, E., Inabe, N., Kanaoka, H., Kojouharov, I., Kubo, T., Kubono, S., Kurz, N., Kuti, I., Lalkovski, S., Lee, E. J., Lee, C. S., Lotay, G., Moon, C. B., Nishizuka, I., Nita, C. R., Patel, Z., Roberts, O. J., Schaffner, H., Shand, C. M., Suzuki, H., Takeda, H., Terashima, S., Vajta, Zs., Kanaya, S., Valiente-Dobòn, J. J., Plompen, A., Hambsch, F. -J., Schillebeeckx, P., Mondelaers, W., Heyse, J., Kopecky, S., Siegler, P., & Oberstedt, S. Isomer-delayed gamma-ray spectroscopy of neutron-rich 166Tb. United States. doi:10.1051/epjconf/201714610009.
Gurgi, L. A., Regan, P. H., Söderström, P. -A., Watanabe, H., Walker, P. M., Podolyák, Zs., Nishimura, S., Berry, T. A., Doornenbal, P., Lorusso, G., Isobe, T., Baba, H., Xu, Z. Y., Sakurai, H., Sumikama, T., Catford, W. N., Bruce, A. M., Browne, F., Lane, G. J., Kondev, F. G., Odahara, A., Wu, J., Liu, H. L., Xu, F. R., Korkulu, Z., Lee, P., Liu, J. J., Phong, V. H., Yagi, A., Zhang, G. X., Alharbi, T., Carroll, R. J., Chae, K. Y., Dombradi, Zs., Estrade, A., Fukuda, N., Griffin, C., Ideguchi, E., Inabe, N., Kanaoka, H., Kojouharov, I., Kubo, T., Kubono, S., Kurz, N., Kuti, I., Lalkovski, S., Lee, E. J., Lee, C. S., Lotay, G., Moon, C. B., Nishizuka, I., Nita, C. R., Patel, Z., Roberts, O. J., Schaffner, H., Shand, C. M., Suzuki, H., Takeda, H., Terashima, S., Vajta, Zs., Kanaya, S., Valiente-Dobòn, J. J., Plompen, A., Hambsch, F. -J., Schillebeeckx, P., Mondelaers, W., Heyse, J., Kopecky, S., Siegler, P., and Oberstedt, S. 2017. "Isomer-delayed gamma-ray spectroscopy of neutron-rich 166Tb". United States. doi:10.1051/epjconf/201714610009. https://www.osti.gov/servlets/purl/1393944.
@article{osti_1393944,
title = {Isomer-delayed gamma-ray spectroscopy of neutron-rich 166Tb},
author = {Gurgi, L. A. and Regan, P. H. and Söderström, P. -A. and Watanabe, H. and Walker, P. M. and Podolyák, Zs. and Nishimura, S. and Berry, T. A. and Doornenbal, P. and Lorusso, G. and Isobe, T. and Baba, H. and Xu, Z. Y. and Sakurai, H. and Sumikama, T. and Catford, W. N. and Bruce, A. M. and Browne, F. and Lane, G. J. and Kondev, F. G. and Odahara, A. and Wu, J. and Liu, H. L. and Xu, F. R. and Korkulu, Z. and Lee, P. and Liu, J. J. and Phong, V. H. and Yagi, A. and Zhang, G. X. and Alharbi, T. and Carroll, R. J. and Chae, K. Y. and Dombradi, Zs. and Estrade, A. and Fukuda, N. and Griffin, C. and Ideguchi, E. and Inabe, N. and Kanaoka, H. and Kojouharov, I. and Kubo, T. and Kubono, S. and Kurz, N. and Kuti, I. and Lalkovski, S. and Lee, E. J. and Lee, C. S. and Lotay, G. and Moon, C. B. and Nishizuka, I. and Nita, C. R. and Patel, Z. and Roberts, O. J. and Schaffner, H. and Shand, C. M. and Suzuki, H. and Takeda, H. and Terashima, S. and Vajta, Zs. and Kanaya, S. and Valiente-Dobòn, J. J. and Plompen, A. and Hambsch, F. -J. and Schillebeeckx, P. and Mondelaers, W. and Heyse, J. and Kopecky, S. and Siegler, P. and Oberstedt, S.},
abstractNote = {Here, this short paper presents the identification of a metastable, isomeric-state decay in the neutron-rich odd-odd, prolate-deformed nucleus 166Tb. The nucleus of interest was formed using the in-flight fission of a 345 MeV per nucleon 238U primary beam at the RIBF facility, RIKEN, Japan. Gamma-ray transitions decaying from the observed isomeric states in 166Tb were identified using the EURICA gamma-ray spectrometer, positioned at the final focus of the BigRIPS fragments separator. The current work identifies a single discrete gamma-ray transition of energy 119 keV which de-excites an isomeric state in 166Tb with a measured half-life of 3.5(4) μs. The multipolarity assignment for this transition is an electric dipole and is made on the basis internal conversion and decay lifetime arguments. Possible two quasi-particle Nilsson configurations for the initial and final states which are linked by this transition in 166Tb are made on the basis of comparison with Blocked BCS Nilsson calculations, with the predicted ground state configuration for this nucleus arising from the coupling of the v(1-/2)[521] and π(3+/2) Nilsson orbitals.},
doi = {10.1051/epjconf/201714610009},
journal = {EPJ Web of Conferences},
number = 10009,
volume = 146,
place = {United States},
year = 2017,
month = 9
}

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