共查询到20条相似文献,搜索用时 31 毫秒
1.
A. Dhal R. K. Sinha P. Agarwal S. Kumar Monika B. B. Singh R. Kumar P. Bringel A. Neusser R. Kumar K. S. Golda R. P. Singh S. Muralithar N. Madhavan J. J. Das A. Shukla P. K. Raina K. S. Thind A. K. Sinha I. M. Govil P. K. Joshi R. K. Bhowmik A. K. Jain S. C. Pancholi L. Chaturvedi 《The European Physical Journal A - Hadrons and Nuclei》2006,27(1):33-36
High-spin states in 78Kr have been studied via the 63Cu (19F, 2p2n)78Kr reaction at a beam energy of 60 MeV using the Indian National Gamma Array (INGA). In this nucleus, lifetimes have been
measured upto the Iπ=22+ level in the yrast positive-parity band and upto the Iπ=15- level in the negative-parity band using the Doppler Shift Attenuation Method (DSAM). The deduced transition quadrupole moments
Qt's are found to decrease with rotational frequency for both the bands. 相似文献
2.
A. Görgen E. Clément A. Chatillon A. Dewald W. Korten Y. Le Coz N. Mărginean B. Melon R. Menegazzo O. Möller Ch. Theisen D. Tonev C. A. Ur K. O. Zell 《The European Physical Journal A - Hadrons and Nuclei》2005,26(2):153-157
Lifetimes of excited states in the ground-state bands of 74Kr and 76Kr were measured using the recoil-distance Doppler-shift and the differential decay curve methods. The states were populated
in the 40Ca(40Ca, α2p) and 40Ca(40Ca, 4p) reactions. Gamma rays were detected with the GASP array which was coupled to the Cologne Plunger device. The results resolve
discrepancies between earlier lifetime measurements and a recent Coulomb excitation experiment. Experimental transition rates
are compared to theoretical calculations. The results support a strong mixing between prolate and oblate configurations for
the low-spin states, and represent an important basis for the interpretation and understanding of the shape coexistence phenomenon
in this mass region. 相似文献
3.
4.
A. Jokinen J.C. Wang J. Äystö P. Dendooven S. Nummela J. Huikari V. Kolhinen A. Nieminen K. Peräjärvi S. Rinta-Antila 《The European Physical Journal A - Hadrons and Nuclei》2000,9(1):9-12
Beta decay of a refractory isotope 118Rh produced in symmetric fission and mass separated by the ion guide technique has been applied for the study of low-lying
excited states of 118Pd. The yrast band in 118Pd has been observed up to a 6+ state and the lowest states of the asymmetric γ-band have been identified. The measured half-life of 118Rh is (300±60)ms. The systematics of the excited states in neutron-rich Pd-isotopes implies the saturation towards an O(6) symmetry at N = 70.
Received: 19 June 2000 / Accepted: 1 August 2000 相似文献
5.
T. Rzaca-Urban W. Urban A. Kaczor J.L. Durell M.J. Leddy M.A. Jones W.R. Phillips A.G. Smith B.J. Varley I. Ahmad L.R. Morss M. Bentaleb E. Lubkiewicz N. Schulz 《The European Physical Journal A - Hadrons and Nuclei》2000,9(2):165-169
Neutron-rich, 88-94Kr nuclei, populated in spontaneous fission of 248Cm, have been studied with EUROGAM 2, by measuring prompt γ-rays. Many new excited states in even-even Kr isotopes have been
identified. For the first time spins and parities were determined experimentally in these nuclei. Our results indicate that
the quadrupole deformation of Kr isotopes will appear only above N = 58, as observed in Sr and Zr nuclei. The newly found 3- level at 1506.4 keV in 90Kr suggests the exsistence of a new region of increased octupole correlations, probably associated with the ν(d
5/2
h
11/2) pair of Δl = Δj = 3 orbitals.
Received: 18 September 2000 / Accepted: 18 October 2000 相似文献
6.
R. Krücken Z. Wang S.J. Asztalos J.A. Becker L.A. Bernstein R.M. Clark M.A. Deleplanque R.M. Diamond P. Fallon N. Fotiades K. Hauschild I.Y. Lee A.O. Macchiavelli G.J. Schmid F.S. Stephens K. Vetter 《The European Physical Journal A - Hadrons and Nuclei》1999,5(4):367-370
Lifetimes of states in the two strongest superdeformed (SD) bands in 193Tl were measured using the Doppler-shift attenuation method. The reaction 176Yb(23Na,6n)193Tl at a beam energy of 129 MeV was used and γ-rays were detected by the Gammasphere array. Quadrupole moments of 18.3(10)
eb and 17.4(10) eb were extracted for SD bands 1 and 2, respectively, using the fractional Doppler-shifts of the SD transitions.
The previously reported linking transitions of these SD bands to normal deformed near yrast levels could not be confirmed.
No other candidates for linking transitions could be established.
Received: 27 April 1999 相似文献
7.
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
8.
M. Sugawara H. Kusakari Y. Igari K. Myojin D. Nishimiya S. Mitarai M. Oshima T. Hayakawa M. Kidera K. Furutaka Y. Hatsukawa 《The European Physical Journal A - Hadrons and Nuclei》1998,1(2):123-124
The high spin states of 143Gd have been studied via the 111Cd(35Cl,1p2n) reaction at 170 MeV. One dipole cascade has been newly found and two dipole cascades have been extended to higher spin states.
A relatively long E2 cascade consisting of irregular transition energies has been found, which has only weak connections to
the other dipole and quadrupole cascades. This resembles the ones recently found in 142,143,144Eu and 144Gd. The dipole and quadrupole cascades have been found to appear by turns in an energy increment of about 0.2 MeV above the
yrast line.
Received: 1 November 1997 相似文献
9.
E. Grodner A. A. Pasternak Ch. Droste T. Morek J. Srebrny J. Kownacki W. Płóciennik A. A. Wasilewski M. Kowalczyk M. Kisieliński R. Kaczarowski E. Ruchowska A. Kordyasz M. Wolińska 《The European Physical Journal A - Hadrons and Nuclei》2006,27(3):325-340
Lifetimes of yrast levels with spins Iπ = 23/2--43/2- in 131La populated in the 122Sn(14N, 5n) reaction at a beam energy of 70MeV are measured by the Doppler Shift Attenuation method. A model of side-feeding population
is presented. The model parameters are determined in an experiment based on the lineshape of γ-transitions from two highest
spin levels and from the intensity distribution along the yrast band. The properties of the h11/2 band in 131La are compared with the theoretical predictions obtained in the framework of the Core-Quasi-Particle Coupling and the self-consistent
Total Routhian Surface models. 相似文献
10.
T. Grahn A. Dewald O. Möller R. Julin C. W. Beausang S. Christen I. G. Darby S. Eeckhaudt P. T. Greenlees A. Görgen K. Helariutta J. Jolie H. Kettunen T. Kröll R. Krücken P. Jones S. Juutinen Y. Le Coz M. Leino A.-P. Leppänen P. Maierbeck B. Melon D. A. Meyer P. Nieminen M. Nyman R. Page J. Pakarinen P. Petkov P. Rahkila B. Saha M. Sandzelius J. Sarén C. Scholey J. Uusitalo 《The European physical journal. Special topics》2007,150(1):121-122
Lifetimes of low-lying yrast states in 186Pb and
194Po have been determined by employing, for the first time, the recoil-decay tagging technique in recoil distance Doppler-shift
lifetime measurements. In addition, lifetime measurements of prolate states in 188Pb up to the 8+ state were carried out using the recoil gating method. The deformation parameters
and
for the prolate (186,188Pb) and the oblate (194Po) bands,
respectively, have been extracted from the measured lifetimes.
27.70.+q– 相似文献
11.
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
12.
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
13.
T. Kautzsch W.B. Walters M. Hannawald K.-L. Kratz V.I. Mishin V.N. Fedoseyev W. Böhmer Y. Jading P. Van Duppen B. Pfeiffer A. Wöhr P. Möller I. Klöckl V. Sebastian U. Köster M. Koizumi J. Lettry H.L. Ravn the ISOLDE Collaboration 《The European Physical Journal A - Hadrons and Nuclei》2000,9(2):201-206
A chemically selective laser ion source has been used in a β-decay study of heavy Ag isotopes into even-even Cd nuclides.
Gamma-spectroscopic techniques in time-resolving event-by-event and multiscaling modes have permitted the identification of
the first 2+ and 4+ levels in 126Cd78, 128Cd80, and tentatively the 2+ state in 130Cd82. From a comparison of these new states in 48Cd with the E(2+) and E(4+)/E(2+) level systematics of 46Pd and 52Te isotopes and several recent model predictions, possible evidence for a weakening of the spherical N = 82 neutron-shell below double-magic 132Sn is obtained.
Received: 13 July 2000 / Accepted: 12 October 2000 相似文献
14.
E. Ideguchi X.H. Zhou Y. Gono S. Mitarai T. Morikawa M. Kidera H. Tsuchida M. Shibata H. Watanabe M. Miyake A. Odahara M. Oshima Y. Hatsukawa S. Hamada H. Iimura M. Shibata T. Ishi T. Kishida M. Ishihara 《The European Physical Journal A - Hadrons and Nuclei》1999,6(4):387-390
High spin states of 146Eu were studied by in-beam gamma ray spectroscopic techniques using 140Ce(10B,4n)146Eu and 139La(13C,6n)146Eu reactions. The level scheme was established up to 10MeV. A new high spin isomer with 10ns half life was found. Configurations
of yrast states were understood by a weak coupling of f7/2 neutron to those of 145Eu.
Received: 2 November 1999 相似文献
15.
H. G. Bohlen R. Kalpakchieva W. von Oertzen T. N. Massey A. A. Ogloblin G. de Angelis M. Milin Ch. Schulz Tz. Kokalova C. Wheldon 《The European Physical Journal A - Hadrons and Nuclei》2007,31(3):279-302
The structure of 17C has been investigated using the three-neutron transfer reaction (12C,9C) on a 14C target at 231MeV incident energy, the reaction Q-value is Q
0 = - 46.930MeV. Eleven new states up to 16.3MeV excitation energy were identified. The same reaction has also been used on
a 12C target ( Q
0 = - 38.787MeV), and excited states in 15C up to 19MeV were observed. In 17C the three transferred neutrons populate (sd )3 configurations on the 14C core. The comparison of levels populated by the (12C,9C) reaction in 17C, 16C and 15C reveals a strong similarity of their properties. This concerns especially nine states in each of the three carbon isotopes,
which show practically the same excitation energies except a constant mean shift of +5.82MeV for 16C and +6.65MeV for 15C with respect to 17C. The triples of states from the three isotopes, which correspond to each other, have also similar widths and cross-section
ratios. It is concluded that the same (sd )3 structures are populated in the three carbon isotopes. The observed levels of 17C are also compared to the levels of 19O with known assignments and to shell model calculations, and their decay properties are discussed. 相似文献
16.
Z. Liu X. Sun X. Zhou X. Lei Y. Guo Y. Zhang X. Chen H. Jin Y. Luo S.X. Wen C.X. Yang G.J. Yuan G.S. Li X.A. Liu W.D. Luo Y.S. Chen 《The European Physical Journal A - Hadrons and Nuclei》1998,1(2):125-135
High-spin states of 117Xe were investigated by means of in-beam γ-ray spectroscopic techniques via the reaction of 28Si bombarding a 92Mo target at beam energies of 100-120 MeV. A positive-parity rotational band decaying into the yrast negative-parity band
by a series of enhanced E1 transitions was observed for the first time, implying the existence of octupole correlations in
117Xe. The B(E1) values increase with spin. The νd5/2 band was firmly established up to 27/2+ and the B(M1)/B(E2) ratios were extracted from the relative intensities of γ-rays in this band. The previously known νh11/2 and νg7/2 [413]5/2+α=−1/2 bands were confirmed and extended up to high spins and two bandcrossings are observed in the latter at ħω=0.33 and
0.44 MeV, respectively. The bandcrossings and configurations of these bands are discussed by TRS and CSM calculations. In
a γ–γ–t measurement, the 11/2− and 7/2− levels were identified as two isomers with half-lives of 59.4±20 ns and 16.5±8.0 ns, respectively.
Received: 17 June 1997 / Revised version: 29 September 1997 相似文献
17.
Deformed configuration mixing shell model based on Hartree-Fock states with extension to include isospin projection (DSMT) for two- and four-particle configurations (generated by particle-hole excitations) is applied to study the structure of the low-lying T = 0, 1 and 2 bands (or levels) in the even-even N = Z nuclei 52Fe and 72Kr. The pf-shell KB3 interaction for 52Fe and a modified Kuos interaction for 72Kr are employed in the calculations. In this first application of DSMT with four-particle T projection, low-spin (J 10) members of the T = 0, 1 and 2 bands in 52Fe are compared with experiment including the known E2 transition strengths. The agreement between DSMT and experiment is reasonably good. Similarly, the low-spin members of the observed (prolate) yrast band in 72Kr are also well described by DSMT. 相似文献
18.
D. Bucurescu Gh. Căta-Danil I. Căta-Danil M. Ivaşcu N. Mărginean C. Rusu L. Stroe C.A. Ur A. Gizon J. Gizon B. Nyakó J. Timár L. Zolnai A.J. Boston D.T. Joss E.S. Paul A.T. Semple C.M. Parry 《The European Physical Journal A - Hadrons and Nuclei》2001,10(3):255-258
High-spin states in the 96Tc nucleus have been studied with the reactions 82Se(19F,5nγ) at 68 MeV and Zn(36S,αpxn) at 130 MeV. Two γ-ray cascades (irregular bandlike structures) have been observed up to an excitation energy of about 10
MeV and spin 21-22?.
Received: 19 January 2001 / Accepted: 30 March 2001 相似文献
19.
Zs. Podolyák P.G. Bizzeti A.M. Bizzeti-Sona S. Lunardi D. Bazzacco A. Dewald A. Algora G. de Angelis E. Farnea A. Gadea D.R. Kasemann T. Klug Th. Kröll S. Lenzi D.R. Napoli C.M. Petrache R. Peusquens C. Rossi Alvarez T. Martinez C.A. Ur 《The European Physical Journal A - Hadrons and Nuclei》2003,17(1):29-36
Lifetimes of excited states in 148Gd were measured using the recoil distance method with a plunger device coupled to the EUROBALL Ge detector array. The differential
decay curve method in coincidence mode allowed the unambiguous determination of lifetimes of more than 20 excited states.
The obtained transition strengths are in good agreement with the shell model calculations. The effect of the Z = 64 subshell closure on the B(E2 : 2+ → 0+) reduced strengths above the N = 82 magic number is discussed.-1
Received: 14 November 2002 / Accepted: 4 February 2003 / Published online: 29 April 2003 相似文献
20.
G. Schönwaßer H. Hübel G.B. Hagemann J. Domscheit A. Görgen B. Herskind G. Sletten J.N. Wilson D.R. Napoli C. Rossi-Alvarez D. Bazzacco R. Bengtsson H. Ryde P.O. Tjøm S.W. Ødegård 《The European Physical Journal A - Hadrons and Nuclei》2002,13(3):291-296
Lifetimes of states in the yrast superdeformed bands of 163Lu and 164Lu were determined in a Doppler-shift attenuation-method experiment. From fractional Doppler shifts and line shapes, average
transition quadrupole moments, Q
t = 8.2-0.6
+1.0 b and 7.1-0.6
+0.5 b, were deduced for one of the bands in 163Lu and 164Lu, respectively. These values are much larger than the quadrupole moment of the normal-deformed yrast band in 163Yb, Q
t = 4.9-0.4
+1.3 b, that was also determined in this experiment. Comparison to cranking calculations indicates that both superdeformed bands
correspond to a local potential energy minimum with a pronounced triaxiality, γ∼ 20°.
Received: 8 November 2001 / Accepted: 9 January 2002 相似文献