Rotational structures and their evolution with spin in {sup 152}Gd.
Abstract
The fusion-evaporation reaction involving a 175 MeV {sup 36}S beam and a {sup 124}Sn target was performed, and the emitted {gamma} rays were observed with the Gammasphere spectrometer. Significant additions to the level scheme of {sup 152}Gd were made in spite of the relative weakness of the {alpha}4n exit channel, being only {approx}2% of the total fusion cross-section. The high-spin behavior of {sup 152}Gd was compared with that of other N=88 nuclei. A striking similarity was observed with {sup 154}Dy and it is therefore suggested that the angular-momentum-induced shape changes that take place in {sup 154}Dy also occur in {sup 152}Gd in the 30--40{h_bar} spin range. This is supported by Cranked Nilsson-Strutinsky calculations which were used to interpret the high-spin bands. It is found that a better agreement between calculation and experiment is obtained if the Z=64 shell gap increases with a decreasing number of valence particles outside the doubly-closed {sub 64}{sup 146}Gd82 nucleus.
- Authors:
- more »
- Publication Date:
- Research Org.:
- Argonne National Lab. (ANL), Argonne, IL (United States)
- Sponsoring Org.:
- USDOE Office of Science (SC); NSF-Florida; UK Engineering and Physical Science Research Council; Swedish Science Research Council
- OSTI Identifier:
- 914961
- Report Number(s):
- ANL/PHY/JA-58683
Journal ID: ISSN 0556-2813; PRVCAN; TRN: US200817%%36
- DOE Contract Number:
- DE-AC02-06CH11357
- Resource Type:
- Journal Article
- Resource Relation:
- Journal Name: Phys. Rev. C; Journal Volume: 75; Journal Issue: 2007
- Country of Publication:
- United States
- Language:
- ENGLISH
- Subject:
- 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; MEV RANGE 100-1000; SPIN; DYSPROSIUM 154; GADOLINIUM 152; TIN 124 TARGET; SULFUR 36 REACTIONS; GAMMA RADIATION; HIGH SPIN STATES
Citation Formats
Campbell, D. B., Laird, R. W., Riley, M. A., Simpson, J., Kondev, F. G., Hartley, D. J., Janssens, R. V. F., Brown, T. B., Carpenter, M. P., Fallon, P., Fischer, S. M., Lauritsen, T., Nisius, D., Ragnarsson, I., LLNL, Texas Lutheran Univ., Florida State Univ., Daresbury Lab., U.S. Naval Academy, SRL, LBNL., DePaul Univ., and Lund Univ.. Rotational structures and their evolution with spin in {sup 152}Gd.. United States: N. p., 2007.
Web. doi:10.1103/PhysRevC.75.064314.
Campbell, D. B., Laird, R. W., Riley, M. A., Simpson, J., Kondev, F. G., Hartley, D. J., Janssens, R. V. F., Brown, T. B., Carpenter, M. P., Fallon, P., Fischer, S. M., Lauritsen, T., Nisius, D., Ragnarsson, I., LLNL, Texas Lutheran Univ., Florida State Univ., Daresbury Lab., U.S. Naval Academy, SRL, LBNL., DePaul Univ., & Lund Univ.. Rotational structures and their evolution with spin in {sup 152}Gd.. United States. doi:10.1103/PhysRevC.75.064314.
Campbell, D. B., Laird, R. W., Riley, M. A., Simpson, J., Kondev, F. G., Hartley, D. J., Janssens, R. V. F., Brown, T. B., Carpenter, M. P., Fallon, P., Fischer, S. M., Lauritsen, T., Nisius, D., Ragnarsson, I., LLNL, Texas Lutheran Univ., Florida State Univ., Daresbury Lab., U.S. Naval Academy, SRL, LBNL., DePaul Univ., and Lund Univ.. Mon .
"Rotational structures and their evolution with spin in {sup 152}Gd.". United States.
doi:10.1103/PhysRevC.75.064314.
@article{osti_914961,
title = {Rotational structures and their evolution with spin in {sup 152}Gd.},
author = {Campbell, D. B. and Laird, R. W. and Riley, M. A. and Simpson, J. and Kondev, F. G. and Hartley, D. J. and Janssens, R. V. F. and Brown, T. B. and Carpenter, M. P. and Fallon, P. and Fischer, S. M. and Lauritsen, T. and Nisius, D. and Ragnarsson, I. and LLNL and Texas Lutheran Univ. and Florida State Univ. and Daresbury Lab. and U.S. Naval Academy and SRL and LBNL. and DePaul Univ. and Lund Univ.},
abstractNote = {The fusion-evaporation reaction involving a 175 MeV {sup 36}S beam and a {sup 124}Sn target was performed, and the emitted {gamma} rays were observed with the Gammasphere spectrometer. Significant additions to the level scheme of {sup 152}Gd were made in spite of the relative weakness of the {alpha}4n exit channel, being only {approx}2% of the total fusion cross-section. The high-spin behavior of {sup 152}Gd was compared with that of other N=88 nuclei. A striking similarity was observed with {sup 154}Dy and it is therefore suggested that the angular-momentum-induced shape changes that take place in {sup 154}Dy also occur in {sup 152}Gd in the 30--40{h_bar} spin range. This is supported by Cranked Nilsson-Strutinsky calculations which were used to interpret the high-spin bands. It is found that a better agreement between calculation and experiment is obtained if the Z=64 shell gap increases with a decreasing number of valence particles outside the doubly-closed {sub 64}{sup 146}Gd82 nucleus.},
doi = {10.1103/PhysRevC.75.064314},
journal = {Phys. Rev. C},
number = 2007,
volume = 75,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
-
The fusion-evaporation reaction involving a 175 MeV {sup 36}S beam and a {sup 124}Sn target was performed, and the emitted {gamma} rays were observed with the Gammasphere spectrometer. Significant additions to the level scheme of {sup 152}Gd were made in spite of the relative weakness of the {alpha}4n exit channel, being only {approx}2% of the total fusion cross-section. The high-spin behavior of {sup 152}Gd was compared with that of other N=88 nuclei. A striking similarity was observed with {sup 154}Dy and it is therefore suggested that the angular-momentum-induced shape changes that take place in {sup 154}Dy also occur in {supmore »
-
$gamma$-$gamma$ CORRELATION MEASUREMENTS OF Sm$sup 152$, Gd$sup 152$ AND Gd$sup 154$: SPIN SEQUENCE, MIXING RATIO, AND g-FACTOR (in German)
Angular-correlation methods were used to establish the spin sequence and the multipele mixing ratio of several gamma -ray cascades in the decay of Eu/sup 152/ Eu/sup 152//sup m/ Eu/sup 1/ s/sup 54/, and to measure the nuclear g-factor of Sm/sup 152/. For liquid sources, only the 123 kev level of Gd/sup 154/ showed attenuation. lt was found that each level in the decay of Eu/sup 152/ to Sm/sup 152/ cor responds to a level of the same spin and parity in the decay of Eu/sup 164/ to Gd/sup 154/. In Gd/sup 154/ an additional 2< s->s level of 1721 kevmore » -
Spin determination and quantized alignment in the superdeformed bands in sup 152 Dy, sup 151 Tb, and sup 150 Gd
The spin of the lowest level observed in the superdeformed band in {sup 152}Dy is determined to be {ital I}{sub 0}=25 rather than the previously assigned {ital I}{sub 0}=22. As a result, we have {ital scrI}{sup (1)}{gt}{ital scrI}{sup (2)} and both {ital scrI}{sup (1)} and {ital scrI}{sup (2)} decrease very slowly with rotational frequency. From the spin determination of the two pairs of identical bands in {sup 152}Dy and {sup 151}Tb{sup *}, {sup 151}Tb and {sup 150}Gd{sup *}, evidence has been obtained to support the assumption of quantized alignments in units of {h bar}/2. -
High-spin states in {sup 152}Gd
High-spin states of {sup 152}Gd have been studied via the {sup 148}Nd({sup 9}Be,5n){sup 152}Gd fusion-evaporation reaction at a beam energy of 54 MeV. The ground-state band, octupole band, and {beta} band have been extended up to spins 20{sup +}, 21{sup -}, and 16{sup +}, respectively. A possible aligned two quasineutron band, which becomes the yrast band above the spin 16{sup +}, was observed for the first time. The kinematic behaviors of the ground-state bands and yrast bands in {sup 152,154}Gd indicate that the shape of {sup 152}Gd may change with increasing rotational frequency and the difference of quadrupole deformations betweenmore »