Magnetic dipole bands in Hg-190: first evidence of excitations across the Z=82 sub-shell in Hg nuclei

A N Wilson; J Timar; I Ahmad; A Astier; F Azaiez; M H Bergstrom; D J Blumenthal; B Crowell; M P Carpenter; L Ducroux; B J P Gall; F Hannachi; H Hubel; T L Khoo; R V F Janssens; A Korichi; T Lauritsen; A Lopez-Martens; M Meyer; D Nisius; E S Paul; M G Porqueth; N Redon; J F Sharpey-Scafer; R Wadsworth; J N Wilson; I Ragnarsson

Magnetic dipole bands in Hg-190: first evidence of excitations across the Z=82 sub-shell in Hg nuclei

A N Wilson, J Timar, I Ahmad, A Astier, F Azaiez, M H Bergstrom, D J Blumenthal, B Crowell, M P Carpenter, L Ducroux, B J P Gall, F Hannachi, H Hubel, T L Khoo, R V F Janssens, A Korichi, T Lauritsen, A Lopez-Martens, M Meyer, D NisiusE S Paul, M G Porqueth, N Redon, J F Sharpey-Scafer, R Wadsworth, J N Wilson, I Ragnarsson

Physics

Research output: Contribution to journal › Article › peer-review

Abstract

An experiment aimed at studying high-spin states in Hg-190 was performed with the Eurogam II array. The data have revealed the presence of cascades of magnetic dipole transitions with some unexpected properties. Unlike the M1 bands previously observed in the heavier tig isotopes, these structures have extremely large B(M1)/B(E2) ratios. The observation of a third dipole band with much lower B(M1)/B(E2) values in the same spin/excitation energy regime suggests that the bands may represent configurations occurring in different minima in the potential energy surface. Configuration-dependent Cranked Nilsson-Strutinsky calculations predict the presence of a minimum in the nuclear potential energy surface at a deformation of epsilon approximate to 0.2, gamma approximate to -90 degrees. occurring when a proton is excited across the Z = 82 shell-gap into an h(9/2) orbital. It is suggested that the bands exhibiting anomalously large B(MI)/B(E2) ratios may be associated with this minimum. (C) 2001 Published by Elsevier Science B.V.

Original language	English
Pages (from-to)	614
Number of pages	9
Journal	Physics Letters B
Volume	505
Issue number	1-4
Publication status	Published - 26 Apr 2001

Keywords

ROTATIONAL BANDS
OBLATE BAND
ISOTOPES

Cite this

Wilson, A. N., Timar, J., Ahmad, I., Astier, A., Azaiez, F., Bergstrom, M. H., Blumenthal, D. J., Crowell, B., Carpenter, M. P., Ducroux, L., Gall, B. J. P., Hannachi, F., Hubel, H., Khoo, T. L., Janssens, R. V. F., Korichi, A., Lauritsen, T., Lopez-Martens, A., Meyer, M., ... Ragnarsson, I. (2001). Magnetic dipole bands in Hg-190: first evidence of excitations across the Z=82 sub-shell in Hg nuclei. Physics Letters B, 505(1-4), 614.

@article{11f3b0f805ca440797fb1757ac754fcf,

title = "Magnetic dipole bands in Hg-190: first evidence of excitations across the Z=82 sub-shell in Hg nuclei",

abstract = "An experiment aimed at studying high-spin states in Hg-190 was performed with the Eurogam II array. The data have revealed the presence of cascades of magnetic dipole transitions with some unexpected properties. Unlike the M1 bands previously observed in the heavier tig isotopes, these structures have extremely large B(M1)/B(E2) ratios. The observation of a third dipole band with much lower B(M1)/B(E2) values in the same spin/excitation energy regime suggests that the bands may represent configurations occurring in different minima in the potential energy surface. Configuration-dependent Cranked Nilsson-Strutinsky calculations predict the presence of a minimum in the nuclear potential energy surface at a deformation of epsilon approximate to 0.2, gamma approximate to -90 degrees. occurring when a proton is excited across the Z = 82 shell-gap into an h(9/2) orbital. It is suggested that the bands exhibiting anomalously large B(MI)/B(E2) ratios may be associated with this minimum. (C) 2001 Published by Elsevier Science B.V.",

keywords = "ROTATIONAL BANDS, OBLATE BAND, ISOTOPES",

author = "Wilson, {A N} and J Timar and I Ahmad and A Astier and F Azaiez and Bergstrom, {M H} and Blumenthal, {D J} and B Crowell and Carpenter, {M P} and L Ducroux and Gall, {B J P} and F Hannachi and H Hubel and Khoo, {T L} and Janssens, {R V F} and A Korichi and T Lauritsen and A Lopez-Martens and M Meyer and D Nisius and Paul, {E S} and Porqueth, {M G} and N Redon and Sharpey-Scafer, {J F} and R Wadsworth and Wilson, {J N} and I Ragnarsson",

year = "2001",

month = apr,

day = "26",

language = "English",

volume = "505",

pages = "614",

journal = "Physics Letters B",

issn = "0370-2693",

publisher = "Elsevier",

number = "1-4",

}

Wilson, AN, Timar, J, Ahmad, I, Astier, A, Azaiez, F, Bergstrom, MH, Blumenthal, DJ, Crowell, B, Carpenter, MP, Ducroux, L, Gall, BJP, Hannachi, F, Hubel, H, Khoo, TL, Janssens, RVF, Korichi, A, Lauritsen, T, Lopez-Martens, A, Meyer, M, Nisius, D, Paul, ES, Porqueth, MG, Redon, N, Sharpey-Scafer, JF, Wadsworth, R, Wilson, JN & Ragnarsson, I 2001, 'Magnetic dipole bands in Hg-190: first evidence of excitations across the Z=82 sub-shell in Hg nuclei', Physics Letters B, vol. 505, no. 1-4, pp. 614.

TY - JOUR

T1 - Magnetic dipole bands in Hg-190: first evidence of excitations across the Z=82 sub-shell in Hg nuclei

AU - Wilson, A N

AU - Timar, J

AU - Ahmad, I

AU - Astier, A

AU - Azaiez, F

AU - Bergstrom, M H

AU - Blumenthal, D J

AU - Crowell, B

AU - Carpenter, M P

AU - Ducroux, L

AU - Gall, B J P

AU - Hannachi, F

AU - Hubel, H

AU - Khoo, T L

AU - Janssens, R V F

AU - Korichi, A

AU - Lauritsen, T

AU - Lopez-Martens, A

AU - Meyer, M

AU - Nisius, D

AU - Paul, E S

AU - Porqueth, M G

AU - Redon, N

AU - Sharpey-Scafer, J F

AU - Wadsworth, R

AU - Wilson, J N

AU - Ragnarsson, I

PY - 2001/4/26

Y1 - 2001/4/26

N2 - An experiment aimed at studying high-spin states in Hg-190 was performed with the Eurogam II array. The data have revealed the presence of cascades of magnetic dipole transitions with some unexpected properties. Unlike the M1 bands previously observed in the heavier tig isotopes, these structures have extremely large B(M1)/B(E2) ratios. The observation of a third dipole band with much lower B(M1)/B(E2) values in the same spin/excitation energy regime suggests that the bands may represent configurations occurring in different minima in the potential energy surface. Configuration-dependent Cranked Nilsson-Strutinsky calculations predict the presence of a minimum in the nuclear potential energy surface at a deformation of epsilon approximate to 0.2, gamma approximate to -90 degrees. occurring when a proton is excited across the Z = 82 shell-gap into an h(9/2) orbital. It is suggested that the bands exhibiting anomalously large B(MI)/B(E2) ratios may be associated with this minimum. (C) 2001 Published by Elsevier Science B.V.

AB - An experiment aimed at studying high-spin states in Hg-190 was performed with the Eurogam II array. The data have revealed the presence of cascades of magnetic dipole transitions with some unexpected properties. Unlike the M1 bands previously observed in the heavier tig isotopes, these structures have extremely large B(M1)/B(E2) ratios. The observation of a third dipole band with much lower B(M1)/B(E2) values in the same spin/excitation energy regime suggests that the bands may represent configurations occurring in different minima in the potential energy surface. Configuration-dependent Cranked Nilsson-Strutinsky calculations predict the presence of a minimum in the nuclear potential energy surface at a deformation of epsilon approximate to 0.2, gamma approximate to -90 degrees. occurring when a proton is excited across the Z = 82 shell-gap into an h(9/2) orbital. It is suggested that the bands exhibiting anomalously large B(MI)/B(E2) ratios may be associated with this minimum. (C) 2001 Published by Elsevier Science B.V.

KW - ROTATIONAL BANDS

KW - OBLATE BAND

KW - ISOTOPES

M3 - Article

SN - 0370-2693

VL - 505

SP - 614

JO - Physics Letters B

JF - Physics Letters B

IS - 1-4

ER -