共查询到20条相似文献,搜索用时 31 毫秒
1.
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
2.
T. Shizuma Y. Toh M. Oshima M. Sugawara M. Matsuda T. Hayakawa M. Koizumi A. Osa Y.H. Zhang Z. Liu 《The European Physical Journal A - Hadrons and Nuclei》2003,17(2):159-165
Excited states in 187Re populated by inelastic scattering of a 500 MeV 82Se beam have been studied by means of in-beam γ-ray spectroscopy. Levels built on the 5/2+[402] and 9/2-[514] one-quasiparticle states were measured up to I
π = (21/2+) and (21/2-), respectively. In addition, several new levels including an isomer at 1682 keV with a half-life of 114(23) ns have been
found. Quasiparticle configurations of the levels and the transition rates are discussed.
Received: 12 December 2002 / Accepted: 13 March 2003 / Published online: 13 May 2003 相似文献
3.
H. Kettunen T. Enqvist M. Leino K. Eskola P.T. Greenlees K. Helariutta P. Jones R. Julin S. Juutinen H. Kankaanpää H. Koivisto P. Kuusiniemi M. Muikku P. Nieminen P. Rahkila J. Uusitalo 《The European Physical Journal A - Hadrons and Nuclei》2003,16(4):457-467
The low-energy nuclear structure and decay properties of the neutron-deficient isotopes 195At and 191Bi have been studied. 195At was produced in the reaction 142Nd(56Fe,p2n)195At and 191Bi as the daughter activity of 195At. The activities were implanted in a position-sensitive silicon detector after being separated from the primary beam by
a gas-filled recoil separator. The 1/2+ intruder state was determined to be the ground state in 195At with an alpha-decay energy of E
α = 6953(3) keV and a half-life T
1/2 = 328(20) ms. Another state with an alpha-decay energy E
α = 7075(4) keV and a half-life T
1/2 = 147(5) ms was found to decay to a 148.7(5) keV excited state in 191Bi for which a spin and parity of 7/2- were deduced. Consequently, the same 7/2- character was assigned to the initial state at 32(7) keV in 195At on the basis of unhindered alpha-decay. The 9/2- state, being the ground state in heavier odd-mass astatine isotopes, was not observed.
Received: 16 September 2002 / Accepted: 19 December 2002 / Published online: 25 March 2003
RID="a"
ID="a"e-mail: heikki.kettunen@phys.jyu.fi
RID="b"
ID="b"Present address: Laboratory of Radiochemistry, P.O. Box 55, FIN-00014, University of Helsinki, Finland.
RID="c"
ID="c"Present address: Radiation and Nuclear Safety Authority, P.O. Box 14, FIN-00881 Helsinki, Finland.
Communicated by W. Henning 相似文献
4.
K. Van de Vel A.N. Andreyev R.D. Page H. Kettunen P.T. Greenlees P. Jones R. Julin S. Juutinen H. Kankaanpää A. Keenan P. Kuusiniemi M. Leino M. Muikku P. Nieminen P. Rahkila J. Uusitalo K. Eskola A. Hürstel M. Huyse Y. Le Coz M.B. Smith P. Van Duppen R. Wyss 《The European Physical Journal A - Hadrons and Nuclei》2003,17(2):167-171
Gamma rays from excited states of 190Po have been observed using the Jurosphere Ge-detector array coupled to the RITU gas-filled separator. They were associated
with a collective band which from spin 4 onwards resembles the prolate rotational bands known in the isotones 188Pb and 186Hg. This indicates that in 190Po the prolate configuration becomes yrast above I = 2. The experimental results are interpreted in a two-band mixing calculation and are in agreement with α-decay data and
potential energy surface calculations.
Received: 10 January 2003 / Accepted: 19 February 2003 / Published online: 7 May 2003 相似文献
5.
The configuration-dependent cranked Nilsson-Strutinsky approach has been employed to study the properties and band structures
at high spin in the Z = N odd-odd nuclei 46V and 50Mn. The observed bands are explained and terminating states are confirmed by the calculations. The calculated and observed
bands are in good agreement without normalization, especially for terminating states. Possible bands with rotation around
the intermediate axis and the effect of γ-deformation on the total energy of several interesting configurations are discussed.
Received: 2 April 2002 / Accepted: 27 January 2003 / Published online: 15 April 2003 相似文献
6.
C.-B. Moon T. Komatsubara Y. Sasaki T. Jumatsu K. Yamada K. Satou K. Furuno 《The European Physical Journal A - Hadrons and Nuclei》2002,14(1):13-16
Excited states of the 119Xe nucleus have been studied by using in-beam γ-ray spectroscopy with the 107Ag ( 16O, p3n) 119Xe fusion-evaporation reaction at a beam energy of 85 MeV. The level scheme of 119Xe has been derived from γ-γ coincidence and γ-γ angular correlation analyses. We have, for the first time, established the
second negative-parity favored and unfavored states built on the 11/2- state, namely the yrare rotational bands in 119Xe. In contrast to the behavior of the yrast bands where the favored states are lying lower in energy, the yrare favored states
were observed to lie above the unfavored band. Such a signature inversion in 119Xe is changed to be normal at I = 12?.
Received: 8 January 2002 / Accepted: 18 April 2002 相似文献
7.
The nuclear spectroscopic quadrupole moments for the πh9/25/2-, 1/2-[541] and the πh11/29/2-, 9/2-[514] isomeric states in 169Ta have been measured employing the time differential perturbed angular-distribution technique following the nuclear reaction
159Tb(16O, 6nγ)169Ta at beam energy 104 MeV. The ratio of the intrinsic quadrupole moments
has been derived as 1.87(13) from the measured quadrupole precession frequencies of the corresponding states. The model-independent
analysis of the equilibrium deformation indicates strong prolate- and oblate-driving nature of the 1/2-[541] and 9/2-[514] orbitals in 169,171Ta isotopes, respectively. 相似文献
8.
T. Hayakawa Y. Toh M. Oshima M. Matsuda Y. Hatsukawa J. Katakura H. Iimura T. Shizuma S. Mitarai M. Sugawara H. Kusakari Y.H. Zhang 《The European Physical Journal A - Hadrons and Nuclei》2002,15(3):299-302
High-spin states of 157Dy were investigated using in-beam γ-ray spectroscopy techniques with a 150Nd(12C, 5n) reaction. Three rotational bands with the h
9/2, i
13/2 and h
11/2 configurations were observed up to (43/2-), 53/2+ and 45/2-, respectively. Interband M1 transitions in the h
11/2 (high-Ω) band were also measured up to the highest-spin state. The high-spin states were well reproduced by calculations
using the tilted-axis-cranking model (TAC). The B(M1)/B(E2) ratio, Routhian and the tilted angle of the angular-momentum vector are found to be in good agreement with the result of
the TAC calculation.
Received: 22 August 2002 / Accepted: 26 September 2002 / Published online: 19 November 2002
RID="a"
ID="a"e-mail: hayakawa@jball4.tokai.jaeri.go.jp
Communicated by W. Henning 相似文献
9.
D. Bucurescu A. Gadea Ghe. Căta-Danil I. Căta-Danil M. Ivaşcu N. Mărginean C. Rusu L. Stroe C.A. Ur 《The European Physical Journal A - Hadrons and Nuclei》2003,16(4):469-474
High-spin states in the 97Tc nucleus have been studied by in-beam γ-ray spectroscopy with the reaction 82Se(19F,4nγ) at 68 MeV incident energy. Excited states have been observed up to about 8 MeV excitation and spin 43/2. The observed
level scheme is compared with results of shell model calculations.
Received: 22 November 2002 / Accepted: 23 December 2002 / Published online: 18 March 2003
RID="a"
ID="a"e-mail: bucurescu@tandem.nipne.ro
RID="b"
ID="b"Present address: INFN, Laboratori Nazionali di Legnaro, Legnaro, Italy.
RID="b"
ID="b"Present address: INFN, Laboratori Nazionali di Legnaro, Legnaro, Italy.
RID="b"
ID="b"Present address: INFN, Laboratori Nazionali di Legnaro, Legnaro, Italy.
RID="c"
ID="c"Present address: Università di Padova, Padova, Italy.
Communicated by C. Signorini 相似文献
10.
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
11.
N. Buforn A. Astier J. Meyer M. Meyer S. Perriès N. Redon O. Stézowski M.G. Porquet I. Deloncle A. Bauchet J. Duprat B.J.P. Gall C. Gautherin E. Gueorguieva F. Hoellinger T. Kutsarova R. Lucas A. Minkova N. Schulz H. Sergolle Ts. Venkova A.N. Wilson 《The European Physical Journal A - Hadrons and Nuclei》2000,7(3):347-353
High-spin states in 113-116Cd have been investigated with the fusion-fission reaction 28Si +176Yb at 145 > MeV. The experiment has been performed with the Eurogam2 array. New rotational bands based on two quasi-particle
states have been observed for even-even cadmium isotopes. A new level scheme based on the 11/2− isomeric state is proposed for 115Cd and the one of 113Cd has been extended to spin (31/2−). The decoupled bands identified in both odd-A nuclei are interpreted as being built upon a low-Ωh11/2 quasi-neutron configuration. Microscopic Hartree-Fock + BCS calculations confirm the prolate deformation in this mass region
especially for the odd cadmium isotopes.
Received: 21 December 1999 / Revised version: 16 February 2000 相似文献
12.
S. Singh R. Chandra P. K. Rath P. K. Raina J. G. Hirsch 《The European Physical Journal A - Hadrons and Nuclei》2007,33(4):375-388
The two-neutrino double-beta decay of 124, 126Xe , 128, 130Te , 130, 132Ba and 150Nd isotopes is studied in the Projected Hartree-Fock-Bogoliubov (PHFB) model. Theoretical 2ν β-β- half-lives of 128, 130Te , and 150Nd isotopes, and 2ν β+β+ , 2ν β+
EC and 2ν ECEC for 124, 126Xe and 130, 132Ba nuclei are presented. Calculated quadrupolar transition probabilities B(E2 : 0+ → 2+) , static quadrupole moments and g -factors in the parent and daughter nuclei reproduce the experimental information, validating the reliability of the model
wave functions. The anticorrelation between nuclear deformation and the nuclear transition matrix element M
2ν is confirmed. 相似文献
13.
Lichang Yin Yunzuo Liu Jingbin Lu Guangyi Zhao Xianfeng Li Xiaoguang Wu Guangsheng Li Shuxian Wen Chunxiang Yang 《The European Physical Journal A - Hadrons and Nuclei》2001,11(4):379-383
High-spin states of 160Lu have been studied through the 144Sm( 19F, 3n) reaction. The previously known πh
11/2⊗υi
13/2 yrast band is extended from I
π = 21- to 25- and a four quasiparticle band with configuration πh
11/2[523]7/2 -⊗υh
9/2[521]3/2 -⊗ (υi
13/2)2 is reported.
Received: 21 May 2001 / Accepted: 19 July 2001 相似文献
14.
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
15.
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
16.
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
17.
Careful review of all the evidence makes it clear that at least three states are important at 12.4-MeV excitation in 20Ne (four, if the broad (2+) at 12.5 MeV is included). The three states are 3 - , 0 + , and 1 + (0+). The latter, which is quite strong in 19F (3He, d) singles, is probably the state observed in coincidence with 6.13-MeV γ-rays in 19F(3He, dγ).
Received: 19 August 2002 / Accepted: 28 October 2002 / Published online: 17 January 2003
RID="a"
ID="a"e-mail: fortune@physics.upenn.edu
Communicated by D. Guerreau 相似文献
18.
H. Röpke J. Brenneisen M. Lickert 《The European Physical Journal A - Hadrons and Nuclei》2002,14(2):159-167
Eight high-spin states in 36Ar below 10MeV excitation energy, among them a prospective J
π = 8- state at 9408keV and the J? 8 levels of the recently discovered superdeformed rotational band, have been observed by n-γ coincidence measurements with
the 33S(α, nγ) reaction at E
α = 14.4 and 13.4MeV. High-spin assignments of, respectively, J
π = 6+ and 5- were obtained for the E
p = 1209 and 1462keV (E
x = 9682 and 9927keV) resonances of the 35Cl (p,γ) reaction by a measurement of γ-ray angular distributions. The spectrum of the high-spin and of the E
x? 7.4MeV levels is decomposed according to the underlying shell model configurations with n = 0, 1, 2, 4 particles excited from the N = 2 into the N = 3 major shell. The role of four-particle excitations, all connected with large prolate distortions, is elucidated for the
entire A = 36-40 mass region.
Received: 21 December 2001 / Accepted: 25 March 2002 相似文献
19.
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
20.
A. Ioffe O. Ermakov I. Karpikhin P. Krupchitsky P. Mikula P. Lukas M. Vrana 《The European Physical Journal A - Hadrons and Nuclei》2000,7(2):197-200
Excited states of 68Ga have been investigated through the 55Mn(16O, 2pn) reaction at projectile energy 55 MeV. The level scheme has been extended up to 7.8 MeV. Altogether six new excited
levels could be identified and twelve previously unobserved γ-transitions have been placed in the modified level scheme.
Received: 19 June 2000 / Accepted: 20 October 2000 相似文献