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1.
Y.H. Zhang S.Q. Zhang W.X. Huang X.H. Zhou X.C. Feng X. Xu X.G. Lei Y.X. Guo S.F. Zhu J.J. He Z. Liu S.J. Wang Y.X. Luo 《The European Physical Journal A - Hadrons and Nuclei》2000,7(1):19-22
An effort has been made to search for the decoupled bands in odd-odd 174Re via the 159Tb(20Ne,5n γ)174Re reaction through excitation functions, K x-γ and γ-γ coincidence measurements. The doubly decoupled band and the semidecoupled
one have been found in this work. Their quasiparticle configurations are proposed to be π1/2−[541] ⊗ν1/2−[521] and π1/2−[541] ⊗νi
13/2, respectively, according to the characteristics of band structures in this mass region. Another band with strongly coupled
character is also reported.
Received: 23 November 1999 / Revised version: 5 January 2000 相似文献
2.
J.H. Ha J.C. Kim C.S. Lee J.Y. Huh C.-B. Moon Y. Gono S. Mitarai T. Morikawa M. Shibata H. Watanabe M. Miyake E. Komatsu A. Odahara E. Ideguchi X.H. Zhou 《The European Physical Journal A - Hadrons and Nuclei》1998,1(3):247-248
High-spin states of odd-odd 168Lu were observed up to 18ħ for the first time using the 159Tb(13C, 4nγ)168Lu reaction at E
13C= 58.5 MeV. γ-γ coincidence, E
γ singles, excitation function, and the DCO ratios were measured. Two rotational bands with signature splitting were populated,
among which the lower-energy band is identified as π 7/2+[404] ⊗ν 5/2+[642] in view of alignment and energy systematics.
Received: 27 October 1997 相似文献
3.
E.S. Paul A.J. Boston S. Courtin P.J. Dagnall J.L. Durell C. Finck B. Gall B. Haas F. Haas F. Hannachi F. Hoellinger J.C. Lisle A. Lopez-Martens J.C. Merdinger N. Rowley H.C. Scraggs O. Stezowski B.J. Varley J.P. Vivien 《The European Physical Journal A - Hadrons and Nuclei》2000,7(4):449-450
The low-spin band structure of neutron-deficient 115
54Xe has been studied following a low-energy (212.3 MeV) 60Ni(58Ni,2pnγ) reaction performed at IReS, Strasbourg, with the Garel+ spectrometer. The relative excitation energies of νh11/2 (isomeric), νg7/2, and νd5/2 bandheads have been established.
Received: 23 March 2000 相似文献
4.
T.R. Saitoh N. Hashimoto G. Sletten R.A. Bark S. Törmänen M. Bergström K. Furuno K. Furutaka G.B. Hagemann T. Hayakawa T. Komatsubara A. Maj S. Mitarai M. Oshima J. Sampson T. Shizuma P.G. Varmette 《The European Physical Journal A - Hadrons and Nuclei》1998,3(3):197-199
High-spin states in 181Ta have been studied via the 176Yb(11B,α2n) reaction at 52 MeV using the PEX array and at 57 MeV using the NORDBALL array, with α-particle detection. The previously
known, Kπ=(7/2)+ ground state band and Kπ=(9/2)− band have been extended to spins (29/2)+ and (31/2)−, respectively. Two new one-quasiparticle bands, the Kπ=(5/2)+ band built on the known (5/2)+ isomer and a Kπ=((1/2)−) band have been observed. Two other rotational bands with three-quasiparticle structure, Kπ=(15/2)− and ((19/2)+ with π(7/2)[404]ν2(1/2)[510](9/2)[624] and π(9/2)[514]ν2(1/2)[510](9/2)[624] configurations, respectively, have been newly observed. The half-life of the Kπ=((19/2)+) bandhead which decays to the head of the (15/2)− band has been measured to be 140(36) ns. However, transitions from the ((19/2)+) state to the (15/2)− band have not been observed.
Received: 26 August 1998 相似文献
5.
S.K. Katoch S.L. Gupta S.C. Pancholi D. Mehta S. Malik G. Shanker L. Chaturvedi R.K. Bhowmik 《The European Physical Journal A - Hadrons and Nuclei》1999,4(4):307-309
High-spin states in the odd-odd 168Lu nucleus, populated in the 154Sm(19F,5n) reaction at a beam energy of 96 MeV, were investigated using in-beam γ-ray spectroscopy techniques. The BC neutron crossing
in the yrast band, based on πg
7/2[404]7/2+⊗νi
13/2[642]5/2+ configuration, occurs at ħω= 0.31 MeV. The two side bands, based on πh
11/2[514]9/2−⊗νi
13/2[642]5/2+ and πh
9/2[541]1/2−⊗νi
13/2[642]5/2+ configurations, show anomalous signature-splitting and signature-inversion in the first one, to occur at ħω= 0.24 MeV. A
moderately delayed BC-crossing is anticipated in the second one.
Received: 15 June 1998 / Revised version: 11 January 1999 相似文献
6.
J. Timár A. Gizon P. Paris J. Genevey J. Gizon F. Hannachi C.F. Liang A. Lopez-Martens J.C. Merdinger B.M. Nyakó B. Weiss L. Zolnai 《The European Physical Journal A - Hadrons and Nuclei》2000,7(1):7-10
High spin states of 126La have been populated using the reaction 116Sn+14N at 68 MeV. γ-rays and conversion electrons were detected with the GAREL array. Multipolarities of the lowest-lying in-band
dipole transitions have been determined from the deduced internal conversion coefficients. Experimental B(M1)/B(E2) ratios
have been derived for the bands and compared with calculated values using the D?nau-Frauendorf geometrical model. Configurations
are proposed for the bands comparing them with cranked shell model calculations and on the basis of the measured B(M1)/B(E2)
ratios. The β-decay of 126La has also been revisited. The population of the 126Ba levels gives a probable spin value of five for the decaying high-spin 126La state with T
1/2≈ 64 s which may indicate a signature inversion in the πh11/2νh11/2 band.
Received: 12 October 1999 相似文献
7.
T. Shizuma K. Furuno K. Hata H. Ishiyama T. Jumatsu M. Kato T. Komatsubara K. Matsuura Y. Sasaki K. Uchiyama T. Hayakawa 《The European Physical Journal A - Hadrons and Nuclei》1998,1(3):245-246
High-spin states in 183Os have been studied by means of in-beam γ-ray spectroscopy. Two isomers with I
π= ((43/2)−) and (43/2)+ have been identified at excitation energies of E
x
= 5.068 and 5.168 MeV. The half-lives are determined as T
1/2= 27 ± 3 and 24 ± 2 ns.
Received: 22 December 1997 相似文献
8.
J. Mrázek M. Honusek A. Špalek J. Bielčík J. Slívová J. Adam A.A. Pasternak 《The European Physical Journal A - Hadrons and Nuclei》1999,5(4):399-408
The results of in-beam investigations of excited states of 99Ru using the 98Mo(α,3n) reaction are presented. Angular distributions of γ–rays and γ–γ coincidences have been measured. Excited states have
been identified up to an energy of E = 5603 keV and spin of Iπ= 31/2−. Mean lifetimes τ have been determined using the DSA method for eleven levels. Aligned angular momenta are discussed and
the probable (νh
11/2) origin of a backbending at frequency about 0.5 MeV was confirmed. The possible role of (νd
5/2) alignment at frequencies above 0.5 MeV was pointed out.
Received: 13 January 1999 / Revised version: 26 March 1999 相似文献
9.
J.Y. Huh C.S. Lee Y.K. Kwon J.Y. Kim Y. Gono T. Morikawa H. Watanabe M. Shibata S. Motomura T. Tsutsumi T. Fukuchi T. Kishida E. Ideguchi X.H. Zhou A. Odahara S. Kubono J.H. Ha M.K. Cheoun C. Lee J.C. Kim C.-B. Moon S.J. Chae Y.K. Kim J.S. Chai 《The European Physical Journal A - Hadrons and Nuclei》2000,7(1):11-14
High-spin states of 155Gd were populated by using the 154Sm(α,3nγ)155Gd reaction at E
α= 33 MeV. γ-γ coincidence, E
γ singles, excitation function, and the DCO ratios were measured. we have identified three intermediate bands with ΔI= 2 feeding the positive yrast band. The bands are interpreted as such candidate bands that are mixed with the negative-parity
ground state band. This observation can provide a plausible explanation for unusually large population of the positive-parity
yrast band observed in a recent Coulomb excitation.
Received: 2 November 1999 相似文献
10.
C. S. Lee J. H. Ha J. H. Lee J. Y. Huh J. C. Kim C. -B. Moon S. J. Chae T. Komatsubara T. Shizuma H. Kimura K. Matsuura K. Kato Y. Sasaki H. Ishiyama K. Furuno 《The European Physical Journal A - Hadrons and Nuclei》2000,8(1):1-3
High-Spin states of odd-odd 166Lu were populated using the 139La(30Si,3nγ)166Lu at a beam energy of 120 MeV. Twelve new γ-rays were placed on top of the previously known two rotational bands built upon πg
7/2⊗νi
13/2 and πh
11/2⊗νi
13/2. Extending high-spin states up to 21+ and 25− for each band, we have observed the onset of band crossing near ħω
c ≈ 0.35 MeV. The band crossing frequency of the yrast πh
11/2⊗νi
13/2 band is consistent with the neutron BC band crossing observed in lighter odd-odd Lu isotopes. 相似文献
11.
N. Hashimoto T.R. Saitoh G. Sletten R.A. Bark M. Bergström K. Furuno T. Komatsubara T. Shizuma S. Törmänen P.G. Varmette 《The European Physical Journal A - Hadrons and Nuclei》1998,2(4):327-330
Abstact: High-spin states in 183Re have been studied using the 176Yb(11B,4n) reaction at 52 and 57 MeV. Two high-K bands have been observed directly by a time-correlated γ-γ coincidence measurement. One of the bands is built on an isomeric
K
π=(25/2)+ state at E
x= 1908 keV with a half-life of 0.82(2) ms. The other band, assigned as K
π=(29/2)− at E
x= 2739 keV, decays to the (25/2)+ band. These bands are interpreted as three-quasiparticle structures, π(5/2)+[402] &⊗ν(9/2)+[624] ⊗ν(11/2)+[615] for the (25/2)+ band and π(9/2)−[514] ⊗ν(9/2)+[624] ⊗ν(11/2)+[615] for the (29/2)− band. The K
π= (29/2)− band becomes strongly Coriolis mixed with increasing spin and is gradually changing into a low-K s-band structure.
Received: 20 April 1998 相似文献
12.
T. Hayakawa M. Oshima Y. Hatsukawa J. Katakura H. Iimura M. Matsuda N. Shinohara Y. Toh S. Mitarai T. Shizuma M. Sugawara H. Kusakari 《The European Physical Journal A - Hadrons and Nuclei》2000,9(2):153-156
The in-beam spectroscopy on N = 91 isotones has been carried out using the 12C + 150Nd reaction. The νi
13/2 and νh
11/2 bands of 153Sm have been extended up to 33/2+ and 31/2-, respectively. Two new γ-rays have been located on the top of the unfavored band with νi
13/2 configuration in 157Dy. Two identical relationships have been established in the low-spin region of the yrast νi
13/2 configuration between 153Sm and 155Gd, and between unfavored bands of 155Gd and 157Dy. Here all these nuclei have the same neutron number N = 91.
Received: 28 June 2000 / Accepted: 20 October 2000 相似文献
13.
R.S. Chakrawarthy B.S. Nara Singh R.G. Pillay 《The European Physical Journal A - Hadrons and Nuclei》1998,3(1):5-8
High spin states in 108In have been established upto ∼ 8 MeV in excitation energy and to a tentative spin of (23−). The data were obtained by in-beam γ-ray spectroscopy using the reaction 93Nb(19F, p3n)108In at a beam energy of 86 MeV. Four sequences of dipole bands and a normal rotational band of E2 γ-transitions have been placed
in the level scheme.
Received: 16 June 1998 相似文献
14.
Y.-J. Ma Y.-Z. Liu H.-B. Sun S. Wen S.-G. Zhou H. Zheng H.-T. Yang J.-D. Huo X.-G. Wu C.-X. Yang 《The European Physical Journal A - Hadrons and Nuclei》1998,2(1):21-23
Three new bands in 174Ta have been identified by using the 160Gd(19F,5n) reaction at beam energies of 87 MeV and 96 MeV. Nilsson configurations are assigned to these bands. In the 9/2−[514]p+5/2−[512]n band, the AB neutron crossing occurs at a rotational frequency of 0.30 MeV. This is indicative of the disappearance of the
evidence for a reduction in neutron pair correlations.
Received: 30 March 1998 相似文献
15.
J.M. Chatterjee S. Basu-Roy S.S. Ghugre S. Chattopadhyay R.P. Singh G.O. Rodrigues R.K. Chattopadhyay R.K. Bhowmik 《The European Physical Journal A - Hadrons and Nuclei》1998,1(1):55-59
A search for new isomers of nanosecond lifetimes were carried out in 153Eu via the 150Nd(7Li,xnγ) reaction. The single particle angular momentum alignment and dynamical moment of inertia estimated from the experimental
data indicate a configuration change at rotational energy ħω∼ 0.30 MeV. A decrease of B(E2) values is also observed at the
same frequency. An isomeric level is identified at an excitation energy of 3100 keV (Jπ=35/2−) which corresponds to this frequency. The lifetime of the level is found to be 8.6 ± 1.3 nanosecond.
Received: 22 April 1997 / Revised version: 26 September 1997 相似文献
16.
Y.H. Zhang S.Q. Zhang Q.Z. Zhao S.F. Zhu H.S. Xu X.H. Zhou Y.X. Guo X.G. Lei J. Lu Q.B. Gou H.J. Jin Z. Liu Y.X. Luo X.F. Sun Y.T. Zhu X.G. Wu S.X. Wen C.X. Yang 《The European Physical Journal A - Hadrons and Nuclei》1998,1(2):119-121
High spin states in 170Ta have been studied via 159Tb(16O,5nγ)170Ta reaction through excitation functions, K X-γ and γ-γ-t coincidence measurements. Three rotational bands have been identified
among which one coupled band and an unfavored δI=2 E2 transition sequence are newly found in this work. The possible quasiparticle
configurations of these bands are discussed.
Received: 7 November 1997 相似文献
17.
C.-B. Moon T. Komatsubara T. Shizuma Y. Sasaki H. Ishiyama T. Jumatsu K. Furuno 《The European Physical Journal A - Hadrons and Nuclei》1999,5(1):13-16
High-spin states in 117I have been studied via the 103Rh(18O, 4n) reaction at a beam energy of 85 MeV. Many deformed rotational bands built on the proton h11/2, g7/2, and g9/2 orbitals have been identified. Among them, an unfavoured rotational band and a quasi-gamma band based on the h11/2 state have been newly observed. Moreover, positive-parity states above Iπ= 35/2+ reported in the previous work have been rearranged. Several energetically favoured states have been assigned to noncollective
oblate states based on various quasiparticle configurations with β2≈ 0.18–0.19 and γ= 60°.
Received: 1 March 1999 相似文献
18.
A.M. El-Badry T. Kuroyanagi S. Mitarai A. Odahara Y. Gono S. Morinobu K. Ogawa 《The European Physical Journal A - Hadrons and Nuclei》1998,3(2):133-138
A recoil distance method was used to measure half-lives of the excited states of 145Sm. The reaction used was 139La(10B, 4n)145Sm. A plunger system was used. Half-lives were determined for two excited states for the first time. The yrast 27/2+ state was found to have a half-life of 1.1 ± 0.2 ns corresponding to the retardation of 3.1 × 10−4 comparing with the single particle estimate of M1. The excitation energy of this state was well reproduced by the shell model
calculation having a mixed configuration of [π{h11/2(g7/2)−2 (d5/2)−1}10−, νf7/2] + [π{h11/2(g7/2)−1}9−,νh9/2]. Another retarded E1 transition was also found in a decay of a 21/2+ state. Its retardation was 1.6 × 10−4 comparing with the single particle value.
Received: 9 September 1997 / Revised version: 12 June 1998 相似文献
19.
T.T.-H. Yau I.J.D. MacGregor J. Ahrens J.R.M. Annand R. Beck D. Branford P. Grabmayr S.J. Hall P.D. Harty T. Hehl D.G. Ireland J.D. Kellie T. Lamparter K. Livingston M. Liang J.A. MacKenzie S. McAllister J.C. McGeorge R.O. Owens M. Sauer R. Schneider D.P. Watts 《The European Physical Journal A - Hadrons and Nuclei》1998,1(3):241-244
The angular distribution of nucleons emitted in the 12C(γ,pn) reaction has been measured using tagged photons at the Mainz microtron MAMI. The variation of the reaction strength
with the polar angles of the two emitted nucleons is reported for Eγ=120−150 MeV. The proton angular distribution peaks at more backward angles than the 2H(γ,p) differential cross section indicating a departure from the simple quasi-deuteron model of 2N photo-emission. The distribution
shape is in reasonable agreement with microscopic theoretical models which include both π- and ρ-exchange.
Received: 3 September 1997 / Revised version: 17 December 1997 相似文献
20.
P. Bhattacharyya C.T. Zhang P.J. Daly B. Fornal Z.W. Grabowski I. Ahmad T. Lauritsen L.R. Morss W. Urban A. Nowak W.R. Phillips J.L. Durell M.J. Leddy A.G. Smith B.J. Varley N. Schulz E. Lubkiewicz M. Bentaleb J. Blomqvist 《The European Physical Journal A - Hadrons and Nuclei》1998,3(2):109-110
By analysis of fission product γ-ray data measured at Eurogam II using a 248Cm source, yrast levels up to about 2 MeV in the N=84 three-particle nucleus 135Sb have been identified. These levels are interpreted as π g7/2ν f7/2
2 and π g7/2ν f7/2h9/2 states with the help of shell model calculations using empirical nucleon-nucleon interactions.
Received: 30 July 1998 相似文献