共查询到20条相似文献,搜索用时 31 毫秒
1.
K. Singh S. Sihotra S. S. Malik J. Goswamy D. Mehta N. Singh R. Kumar R. P. Singh S. Muralithar E. S. Paul J. A. Sheikh C. R. Praharaj 《The European Physical Journal A - Hadrons and Nuclei》2006,27(3):321-324
The collective band structures of the 125Cs nucleus have been investigated by in-beam γ-ray spectroscopic techniques following the 110Pd ( 19F, 4n) reaction at 75MeV. The previously known level scheme, with rotational bands built on πg7/2, πg9/2 and πh11/2 orbitals, has been extended and evolves into bands involving rotationally aligned ν(h11/2)2 and π(h11/2)2 quasiparticles. A strongly coupled band has been reassigned a high-K πh11/2 ⊗ νg7/2 ⊗ νh11/2 three-quasiparticle configuration and a new side band likely to be its chiral partner has been identified. Configurations
assigned to various bands are discussed in the framework of Principal/Tilted Axis Cranking (PAC/TAC) model calculations. 相似文献
2.
R. Kumar D. Mehta N. Singh H. Kaur A. Görgen S. Chmel R.P. Singh S. Murlithar 《The European Physical Journal A - Hadrons and Nuclei》2001,12(1):5-8
The band structures built on the 5- isomeric state ( T
1/2 = 3.46 m) in the doubly odd 130Cs nucleus have been established up to I = 24? via the 124Sn(11B, 5n)130Cs reaction. The previously observed bands based on the πh
11/2⊗νh
11/2, πg
7/2⊗νh
11/2 and πd
5/2⊗νh
11/2 configurations and a positive-parity side band with multiple connections to the α = 0 signature partner of the yrast πh
11/2⊗νh
11/2 band have been extended to higher spins. A new band based on the πh
11/2⊗νg
7/2 configuration is observed. The yrast πh
11/2⊗νh
11/2 band exhibits anomalous signature splitting whose magnitude decreases up to spin 15 and then increases without restoring
the normal signature splitting.
Received: 20 February 2001 / Accepted: 9 May 2001 相似文献
3.
Y. H. Zhang T. Hayakawa M. Oshima Y. Toh J. Katakura Y. Hatsukawa M. Matsuda N. Shinohara T. Ishii H. Kusakari M. Sugawara T. Komatsubara 《The European Physical Journal A - Hadrons and Nuclei》2000,8(4):439-442
High spin states in 178Ir have been studied via the 152Sm(31P, 5nγ)178Ir reaction through excitation functions, X-γ and γ-γ-t coincidence measurements. According to the band structure characteristics
and the measured intraband B(M1)/B(E2) ratios, two rotational bands are identified and assigned to be associated with the πh
9/2⊗νi
13/2 and πh
11/2⊗νi
13/2 configurations, respectively. Both bands show the signature inversion feature.
Received: 23 March 2000 / Accepted: 31 July 2000 相似文献
4.
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
5.
X. H. Zhou L. Ma Y. B. Xing Y. H. Zhang Y. X. Guo X. G. Lei C. Y. Xie M. Oshima Y. Toh M. Koizumi A. Osa Y. Hatsukawa M. Sugawara M. M. Ndontchueng 《The European Physical Journal A - Hadrons and Nuclei》2006,28(3):271-275
Excited states in 188Tl have been studied experimentally using the 157Gd (35Cl, 4n) reaction at a beam energy of 170MeV. A rotational band built on the πh
9/2 ⊗ νi
13/2 configuration with oblate deformation has been established for 188Tl. Based on the structure systematics of the oblate πh
9/2 ⊗ νi
13/2 bands in the heavier odd-odd Tl nuclei, we have tentatively proposed spin values for the new band in 188Tl. The πh
9/2 ⊗ νi
13/2 oblate band in 188Tl shows low-spin signature inversion, and it can be interpreted qualitatively by the two-quasiparticle plus rotor model including
a J-dependent p-n residual interaction. 相似文献
6.
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
7.
Zhong Liu Yuhu Zhang Yingjun Ma Y. Sasaki K. Yamada H. Oshima H. Yokose M. Ishizuka T. Komatsubara K. Furuno 《中国科学G辑(英文版)》2003,46(4):390-397
Excited states of125Sb have been studied using in-beam γ spectroscopy techniques via the124Sn(7Li, α2n) reaction at a beam energy of 32 MeV. A high-spin level scheme including 21 new γ-transitions and 14 new excited states
have been established. Three isomers have been identified at 1970, 2110 and 2471 keV and the ranges of their half-lives have
been estimated from the delayed coincidence data. The level structure of125Sb is discussed in terms of particle-core excitation coupling. With the help of empirical shell model calculations the three
isomers are proposed to have three-quasiparticle πg7/2⊗v(h
11/2
s
1/2)5−, πg7/2⊗v(h
11/2
d
3/2)7− and πg7/2⊗v(h
112/2)10
+ configurations, respectively. 相似文献
8.
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
9.
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
10.
F.G. Kondev M.A. Riley T.B. Brown R.M. Clark M. Devlin P. Fallon D.J. Hartley I.M. Hibbert D.T. Joss D.R. LaFosse R.W. Laird F. Lerma M. Lively P.J. Nolan N.J. O'Brien E.S. Paul J. Pfohl D.G. Sarantites R.K. Sheline S.L. Shepherd J. Simpson R. Wadsworth 《The European Physical Journal A - Hadrons and Nuclei》1998,2(3):249-251
The quadrupole moment for the πg
9/2⊗νh
11/2 band in the 130>Pr nucleus has been measured using the Doppler-shift attenuation method. A centroid shift analysis was carried out and a value
of Q0=6.1±0.4 eb, corresponding to an axial prolate deformation of β2=0.35(3), has been determined. This is the first direct experimental confirmation of the deformation-driving character of
the πg
9/2 orbital in an odd-odd nucleus in the A≃135 superdeformed region.
Received: 23 April 1998 相似文献
11.
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
12.
T. Bäck B. Cederwall K. Lagergren R. Wyss A. Johnson P. Greenlees D. Jenkins P. Jones D.T. Joss R. Julin S. Juutinen A. Keenan H. Kettunen P. Kuusiniemi M. Leino A.-P. Leppänen M. Muikku P. Nieminen J. Pakarinen P. Rahkila J. Uusitalo 《The European Physical Journal A - Hadrons and Nuclei》2003,17(1):1-5
The decay out of the πh
11/2νh
11/2 band to the known low-energy levels in 132La was studied using the reaction 100Mo + 36S at 160 MeV beam energy. The low-energy level scheme has been further developed and unambiguous spin and parity values have
been assigned to the levels connecting the band to the 6- isomeric state. According to the new level scheme the spins in the πh
11/2νh
11/2 band are shifted up by one unit compared to the earlier tentative experimental values. The obtained new spins prove the existence
of signature inversion in 132La and give further support to the spin assignments made for the πh
11/2νh
11/2 bands in the neighbouring odd-odd La isotopes from level energy systematics.
Received: 7 May 2002 / Accepted: 31 October 2002 / Published online: 17 January 2003
RID="a"
ID="a"e-mail: timar@atomki.hu
RID="b"
ID="b"Present address: Dipartimento di Matematica e Fisica, Università di Camerino, via Madonna delle Carceri, I-62032 Camerino, Italy.
Communicated by J. ?yst? 相似文献
13.
J. Genevey J.A. Pinston H. Faust C. Foin S. Oberstedt M. Rejmund 《The European Physical Journal A - Hadrons and Nuclei》2000,9(2):191-195
In this work we have identified and studied the decay of two new microsecond isomers 19/2- and 23/2+ in 131Sb. This neutron-rich nucleus was produced by thermal neutron-induced fission of 241Pu. The detection is based on time correlation between fission fragments selected by the LOHENGRIN spectrometer at ILL (Grenoble)
and the γ-rays or conversion electrons from isomers. These new data on high-spin states complete the level scheme previously
obtained from β-decay. A large fraction of the members of the πg
7/2ν(h
11/2
-1
d
3/2
-1) and πg
7/2νh
11/2
-2 multiplets are now known and were compared with a multi-particle shell model calculation.
Received: 7 June 2000 / Accepted: 19 September 2000 相似文献
14.
Y.H. Zhang M. Oshima Y. Toh M. Koizumi A. Osa T. Shizuma T. Hayakawa M. Sugawara H. Kusakari T. Morikawa S.X. Wen L.H. Zhu 《The European Physical Journal A - Hadrons and Nuclei》2002,13(4):429-433
The 109,111,113Rh nuclei have been produced as fission fragments in the fusion reaction 18O + 208Pb at 85 MeV. Their level schemes have been built from gamma-rays detected using the Euroball IV array. High-spin states of
the neutron-rich 111,113Rh nuclei have been identified for the first time. Several rotational bands with the odd proton occupying the πg
9/2, πp
1/2 and π(g
7/2/d
5/2) sub-shells have been observed. A band of low-energy transitions has been identified at excitation energy around 2 MeV in
109,111Rh, which can be interpreted in terms of three-quasiparticle excitation, πg
9/2νh
11/2νg
7/2/d
5/2. In addition another structure built on states located at low excitation energy (608 keV in 111Rh, 570 keV in 113Rh) points out that, as already observed in the lighter isotopes 107,109Rh, triaxial deformation plays a role in the neutron-rich Rh isotopes well beyond the mid-shell.
Received: 15 July 2002 / Accepted: 9 October 2002 / Published online: 3 December 2002
RID="a"
ID="a"e-mail: porquet@csnsm.in2p3.fr
RID="b"
ID="b"Present address: CSNSM IN2P3-CNRS and Université Paris-Sud 91405 Orsay, France.
RID="c"
ID="c"Present address: CEA/Saclay, DSM/DAPNIA/SPhN, 91191 Gif-sur-Yvette Cedex, France.
Communicated by D. Schwalm 相似文献
15.
X. L. Che S. J. Zhu M. L. Li Y. J. Chen Y. N. U H. B. Ding L. H. Zhu X. G. Wu G. S. Li C. Y. He Y. Liu 《The European Physical Journal A - Hadrons and Nuclei》2006,30(2):347-350
High-spin states in the 135Ba nucleus have been studied with the reaction 130Te(9Be, 4n) at a beam energy of 45 MeV. The level scheme based on the h
11/2 isomer has been expanded with spins up to 35/2 ℏ. At low spins, the yrast collective structure built on the ν h
11/2
-1 multiplet may show a transitional shape with γ > 30° according to the systematical behavior observed in neighboring nuclei as well as the calculations of the triaxial rotor-plus-particle
model. The configurations for several high-spin states have been discussed from a systematical comparison with neighboring
isotones. 相似文献
16.
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
17.
L. H. Zhu Z. L. Zhang X. G. Wu F. R. Xu G. S. Li Z. M. Wang C. Y. He Y. Wang R. Meng H. B. Sun R. G. Ma X. Z. Cui Y. Liu S. X. Wen Y. Zheng A. Pasternak H. Y. Zhou Y. Z. Liu C. X. Yang 《The European Physical Journal A - Hadrons and Nuclei》2006,27(2):137-141
High-spin states in 171Ta were populated through the heavy-ion fusion-evaporation reaction 157Gd (19F, 5n)171Ta at 105MeV beam energy. Lifetimes of the levels of the πh9/21/2[541] band have been measured by using the Doppler shift attenuation method. The transition quadrupole moments ( Qt) and the quadrupole deformation (β2) have been extracted. Both β2 and Qt values decrease slightly with increasing rotational frequency. The average β2 value of 0.26 is 18% larger than that of the πh11/2 9/2[514] band. Total Routhian Surface calculations have been performed with the non-axial deformed Woods-Saxon potential
and the predicted values of the quadrupole deformation β2 are in good agreement with that deduced from our lifetime measurement. The shape-driving effect is discussed. 相似文献
18.
D. Sohler Zs. Dombrádi J. Blomqvist J. Cederkäll J. Huijnen M. Lipoglavšek M. Palacz A. Atac C. Fahlander H. Grawe A. Johnson A. Kerek W. Klamra J. Kownacki A. Likar L.-O. Norlin J. Nyberg J. Persson D. Seweryniak G. de Angelis P. Bednarczyk D. Foltescu D. Jerrestam S. Juutinen E. Mäkelä M. de Poli H.A. Roth T. Shizuma Ö. Skeppstedt G. Sletten J. Timár S. Törmänen M. Weiszflog 《The European Physical Journal A - Hadrons and Nuclei》2003,16(2):171-175
Excited states of 99Ag were populated via the 50Cr + 58Ni (261 MeV) reaction using the NORDBALL detector array equipped with charged-particle and neutron detector systems for reaction
channel separation. On the basis of the measured γγ-coincidence relations and angular distribution ratios a significantly
extended level scheme has been constructed up to E
x ∼ 7.8 MeV and I = 35/2. The experimental results were described within the framework of the shell model. Candidates for states fully aligned
in the πg
9/2
-3ν(d
5/2, g
7/2)2 valence configuration space were found at 4109 and 6265 keV.
Received: 18 June 2002 / Accepted: 11 October 2002 / Published online: 4 February 2003
RID="a"
ID="a"e-mail: sohler@atomki.hu
Communicated by J. ?yst? 相似文献
19.
D. Hojman J. Sauvage B. Roussière M. A. Cardona G. Marguier A. Wojtasiewicz J. Genevey A. Gizon F. Ibrahim A. Knipper F. Le Blanc J. Obert J. Oms 《The European Physical Journal A - Hadrons and Nuclei》2007,33(2):193-212
Low-spin states of 182Ir were populated through the β+ /EC decay of 182Pt . Two strong E2 transitions were observed for the first time: a 25.7keV transition in 182Ir and a 34.0keV transition in Re of probable mass A = 178 . Spin and parity, I
π = 3+ , are firmly assigned to the 182Ir ground state (g.s.). For the excited states, the parity is established and the spin determined or restricted. These assignments
support most of the interpretations of the level structure previously suggested. The systematics for the known 5+ → 3+ transitions in π h
9/2 ⊗ ν 1/2-[521] bands is presented. Using a semi-microscopic two-quasiparticle axial-rotor coupling model, particle configurations have
been attributed or suggested for most of the coupled states lying at low energy in 182Ir . 相似文献
20.
Yuhu Zhang Furong Xu Jianjun He Zhong Liu Xiaohong Zhou Zaiguo Gan M. Oshima T. Hayakawa Y. Toh T. Shizuma J. Katakura Y. Hatsukawa M. Matsuda H. Kusakari M. Sugawara K. Furuno T. Komatsubara T. Une Shuxian Wen Zhimin Wang 《中国科学G辑(英文版)》2003,46(4):382-389
High-spin states in182Au have been produced and studied via the152Sm(35Cl,5nγ)182Au reaction. The level scheme consisting of the πh
9/2⊗νi
13/2 and πi
13/2⊗νi
13/2 bands has been established for the first time. The low spin signature inversion in both bands has been found. The observed
signature inversion phenomena can be interpreted qualitatively using the pairing and deformation self-consistent cranked Wood-Saxon
calculations. 相似文献