共查询到20条相似文献,搜索用时 46 毫秒
1.
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
2.
K. Uchiyama K. Furuno T. Shizuma M. Sugita M. Kato Y. Tokita M. Murasaki N. Hashimoto H. Takahashi T. Komatsubara K. Matsuura T. Tanaka Y. Sasaki 《The European Physical Journal A - Hadrons and Nuclei》1998,2(1):13-15
The lifetime of the first 2+ state in the nucleus 124Ba has been measured by γ-γ coincidence recoil-distance Doppler shift method. The 109Ag(19F, 4n)124Ba reaction at a beam energy of 75 MeV was employed to populate excited states in 124Ba. The mean lifetime was determined to be 275(12) ps using the differential decay curve method. The value of B(E2;01
+→ 21
+) for 124Ba deduced from the lifetime is in reasonable agreement with the prediction of the proton-neutron interacting boson model(IBM-2)
without Pauli blocking effect.
Received: 23 February 1998 相似文献
3.
K. Jessen M. Bergström P. von Brentano A. Dewald B. Herskind H. Meise C. Schumacher G. Sletten O. Stuck D. Weißhaar I. Wiedenhöver J. Wrzesinski 《The European Physical Journal A - Hadrons and Nuclei》1998,2(2):113-114
An in-beam experiment with the reaction 122Sn(27Al,4np) at 127 MeV was performed at the Nordball multi-detector array in Roskilde. It provided evidence for a new high-spin
isomer in 144Sm. This isomer with T
1/2= (2.6 ± 0.5) ns at an excitation energy E
x= 9232 keV seems to belong to a family of isomers of similar configuration in neighbouring N= 82 nuclei.
Received: 16 November 1997 相似文献
4.
O. Vogel R.S. Chakrawarthy A. Dewald P. Petkov K. Jessen J. Gableske P. von Brentano D. Bazzacco A. Gizon J. Gizon S. Lunardi D.R. Napoli P. Pavan C. Rossi Alvarez I. Wiedenhöver 《The European Physical Journal A - Hadrons and Nuclei》1999,4(4):323-325
High spin states in 128Ba have been investigated with the fusion–evaporation reaction 96Zr(36S,4n)128Ba at a beam energy of 150 MeV with the GASP-spectrometer at INFN in Legnaro, Italy. The level scheme could be extended to
higher spins and six-quasiparticle states have been observed. The deduced alignments are compared to the predictions of previously
reported cranked shell model calculations.
Received: 4 January 1999 相似文献
5.
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
6.
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
7.
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
8.
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
9.
W. Urban N. Schulz M. Bentaleb E. Lubkiewicz J. L. Durell M. J. Leddy M. A. Jones W. R. Phillips A. G. Smith B. J. Varley I. Ahmad L. R. Morss 《The European Physical Journal A - Hadrons and Nuclei》2000,8(1):5-7
Excited levels in 141Xe, populated in spontaneous fission of 248Cm, were studied by means of prompt -ray spectroscopy, using the EUROGAMM2 array. Level scheme of 141Xe obtained in this work shows patterns characteristic of simplex symmetry with s=+i and s=-i bands present but low value of D0 moment indicates that octupole correlations in Xe isotopes are systematically lower than in Ba nuclei.
Received: 9 March 2000 / Accepted: 4 May 2000 相似文献
10.
G. Lhersonneau B. Pfeiffer J. Alstad P. Dendooven K. Eberhardt S. Hankonen I. Klöckl K.-L. Kratz A. Nähler R. Malmbeck J.P. Omtvedt H. Penttilä S. Schoedder G. Skarnemark N. Trautmann J. Äystö 《The European Physical Journal A - Hadrons and Nuclei》1998,1(3):285-297
The decay of 111Ru obtained from fast on-line chemical and mass separation has been investigated by β-γ-t and γ-γ coincidence techniques. Earlier spin and parity assignments of 111Rh levels based on extrapolations of level systematics are confirmed. In particular, the K=1/2 intruder band is supported
by the hindrance of E2 transitions between deformed and spherical states and enhancement of intraband E2 transitions. The
excitation energies of intruder band members in Rh isotopes show a minimum at 109Rh64, with two neutrons less than 111Rh at the N=66 midshell. This trend, which differs from the one in the higher-Z neighbouring elements Ag and Cd with minima
at N=66, follows the evolution of deformation observed in the lower-Z elements Ru and Mo.
Received: 25 June 1997 / Revised version: 10 September 1997 相似文献
11.
A.A. Pasternak J. Srebrny A.D. Efimov V.M. Mikhajlov E.O. Podsvirova Ch. Droste T. Morek S. Juutinen G.B. Hagemann M. Piiparinen S. Törmänen A. Virtanen 《The European Physical Journal A - Hadrons and Nuclei》2002,13(4):435-448
Lifetimes of excited states in 118Te have been measured using the Doppler Shift Attenuation (DSA) and Recoil Distance (RD) methods in the 109Ag(13C, p3n) reaction at a beam energy of 54 MeV. Lifetime values of the ground-state band levels with spins I
π = 2+-16+ have been obtained. The excitation energies and B(E2) values are interpreted in the framework of a version of IBFM ( IBM + 2qp) with the maximum boson number exceeding its standard
value. A satisfactory agreement with experimental level scheme and B(E2) values for the ground-state band is achieved.
Received: 7 June 2001 / Accepted: 7 February 2002 相似文献
12.
M. Sugawara H. Kusakari T. Murakami T. Kohno 《The European Physical Journal A - Hadrons and Nuclei》1998,1(3):237-239
A new rotational band has been observed in 167Lu by 152Sm (19F,4n)reaction at the HI-13 tandem accelerator of CIAE in Beijing. The high spin transition energies of the new band are almost
identical to the triaxial superdeformed bands recently discovered in 163Lu and 165Lu. This new band is predicted as a triaxial superdeformed band by total routhian surface calculations.
Received: 6 October 1997 相似文献
13.
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
14.
P. Mohr C. Hutter K. Vogt J. Enders T. Hartmann S. Volz A. Zilges 《The European Physical Journal A - Hadrons and Nuclei》2000,7(1):45-47
The half-lives of the platinum isotopes 189,191,197Pt and of the 4-day isomer in 195mPt have been measured with high precision using the photoactivation technique. The γ-ray activity was counted over several
half-lives with a high-purity germanium detector. The measured half-lives are: T1/2(189Pt) = 12.1 ± 1.5 h; T1/2(191Pt) = 2.862 ± 0.007 d; T1/2(197Pt) = 19.96 ± 0.05 h; T1/2(195mPt) = 4.0104 ± 0.0047 d.
Received: 13 September 1999 相似文献
15.
J. Simpson M.A. Riley R.W. Laird D.J. Hartley F.G. Kondev J. Sweeney A.N. Wilson S.J. Gale M.A. Bentley A.M. Bruce R. Chapman R.M. Clark D.M. Cullen P. Fallon P.D. Forsyth S.J. Freeman P.M. Jones J.C. Lisle A.O. Macchiavelli J.F. Sharpey-Schafer A.G. Smith J.F. Smith D.M. Thompson 《The European Physical Journal A - Hadrons and Nuclei》1998,1(3):267-274
A series of new strongly coupled high-K, multi-quasiparticle structures have been observed in the light erbium transitional
nuclei, 159Er and 160Er. The interpretation of these bands is discussed within the framework of the cranked shell model. These sequences, when
taken together with the existing quasiparticle excitations, form a near complete set of low-lying, multi-quasiparticle structures
on which a coherent series of aligned angular momentum, band crossing and blocking arguments can be based. The measured B(M1)/B(E2)
ratios are compared with geometrical calculations to test the proposed configuration assignments.
Received: 19 November 1997 相似文献
16.
T. Morek K. Starosta Ch. Droste D. Fossan G. Lane J. Sears J. Smith P. Vaska 《The European Physical Journal A - Hadrons and Nuclei》1998,3(2):99-101
High spin states in 126Ce and 127Pr were populated via heavy ion reactions with 182-MeV 35Cl projectiles on a thick 96Ru target. Prompt γ–γ coincidences were measured. New states in 126Ce and 127Pr were found. The results are discussed in the framework of the core–quasiparticle coupling model.
Received: 16 June 1998 相似文献
17.
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
18.
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
19.
A. Dewald A. Schmidt G. Alexius O. Vogel R.S. Chakrawarthy D. Bazzacco P. von Brentano A. Gizon J. Gizon S. Lunardi D.R. Napoli P. Pavan C. Rossi Alvarez I. Wiedenhöver 《The European Physical Journal A - Hadrons and Nuclei》1998,3(2):103-105
High spin states in 127Ba have been investigated with the fusion–evaporation reaction 96Zr(36S,5n)127Ba at a beam energy of 150 MeV with the GASP-spectrometer at INFN in Legnaro, Italy. The level scheme could be extended to
high spins resulting in the observation of five-quasiparticle states. Altogether 15 band structures were placed in the level
scheme.
Received: 3 July 1998 相似文献
20.
E. Costanzo A. Cunsolo A. Foti O.Yu. Goryunov M. Lattuada V.V. Ostashko L. Putaggio S. Romano C. Spitaleri A. Tumino D. Vinciguerra Yu Xian 《The European Physical Journal A - Hadrons and Nuclei》1999,5(1):69-75
8Begs coincidences with 12C, 8Begs and α-particles produced in the 12C +12C interaction at 65 MeV have been measured in a wide in-plane angular range. The 3 −8Begs final state is found to be produced, even if poor statistics prevent any identification of the 16O states involved in the first stage of the process. The 8Begs−α and 8Begs−12C coincidence yields are found to be due to 12C and 16O excited states, decaying into the 8Begs+α and 12C +α systems, respectively.
Received: 15 June 1998 / Revised version: 4 December 1998 相似文献