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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.
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
3.
R. K. Sinha A. Dhal 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 K. S. Thind A. K. Sinha I. M. Govil R. K. Bhowmik J. B. Gupta P. K. Joshi A. K. Jain S. C. Pancholi L. Chaturvedi 《The European Physical Journal A - Hadrons and Nuclei》2006,28(3):277-281
High-spin states in 79Rb were populated in the reaction
at E(beam) = 60 MeV. The lifetimes of the excited states of the
positive-parity yrast band and of the
negative-parity band in 79Rb were measured by the Doppler Shift Attenuation Method. The deduced transition quadrupole moments Qt are found to have a decreasing trend with rotational frequency for both the bands, consistent with those found experimentally
in neighbouring nuclei.
An erratum to this article is available at . 相似文献
4.
5.
K. Higashiyama N. Yoshinaga 《The European Physical Journal A - Hadrons and Nuclei》2007,33(4):355-374
A simple model is applied to the yrast and yrare states based on the νh
11/2 ⊗ πh
11/2 configuration in the doubly-odd nuclei around the mass 130. In the model, the basis state is constructed by one neutron and
one proton both in the 0h
11/2 orbital, and by the collective core which couples with the two particles through a quadrupole interaction. The model reproduces
quite well the overall energy levels and the electromagnetic transitions. The analysis of the yrast and yrare states reveals
that the angular-momentum configuration of the neutron and the proton in the yrast states is different from that in the yrare
states, when the two particles are weakly coupled with the quadrupole collective excitations of the core. The strong even-odd
staggering of the ratios B(M1;I → I - 1)/B(E2;I → I - 2) for the yrast states is described by the chopsticks-like motion of two angular momenta of the neutron and the proton. 相似文献
6.
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
7.
E. O. Lieder A. A. Pasternak R. M. Lieder A. D. Efimov V. M. Mikhajlov B. G. Carlsson I. Ragnarsson W. Gast Ts. Venkova T. Morek S. Chmel G. de Angelis D. R. Napoli A. Gadea D. Bazzacco R. Menegazzo S. Lunardi W. Urban Ch. Droste T. Rzaca-Urban G. Duchêne A. Dewald 《The European Physical Journal A - Hadrons and Nuclei》2008,35(2):135-158
For a level scheme investigation of 142Gd an experiment with the γ -spectrometer EUROBALLIII has been carried out and lifetimes have been measured with EUROBALL
IV using the Doppler-shift attenuation method. The high-spin states have been populated in these experiments by means of the
99Ru(48Ti, 2p3n) reaction at a beam energy of 240MeV and the 114Sn(32S, 2p2n) reaction at 160MeV, respectively. Reduced E2 transition probabilities B(E2) were determined for 15 members of four quadrupole bands. For the interpretation of the positive-parity even-spin quadrupole
bands, calculations in the cranked Nilsson-Strutinsky as well as interacting boson models have been performed. From the former
calculations it was concluded that the high-spin states of the (+ , 0)1 band in 142Gd represent a triaxial nucleus rotating around the longest principal axis. 相似文献
8.
M. Weiszflog G. de Angelis A. Axelsson D. Bazzacco F. Becker M. De Poli J. Eberth C. Fahlander A. Gadea S. Lunardi D.R. Napoli J. Nyberg C. Rossi Alvarez B. Rubio D. Rudolph S. Skoda H.G. Thomas R. Wyss 《The European Physical Journal A - Hadrons and Nuclei》2001,11(1):25-38
High-spin states in the nuclei 63Ga and 65Ga were studied following the reaction 32S + 40Ca at a reaction energy of 125 MeV and using the GASP γ-ray spectrometer in combination with the ISIS charged-particle detector
system. In addition to low-lying negative-parity states with single-particle character, rotational-like cascades built on
the 9/2+ and 19/2- states have been observed in both nuclei. Sidebands with negative parity in 63Ga and positive parity in 65Ga could be established. The experimental results are compared with Total Routhian Surface calculations which describe the
nuclei as moderately deformed (β2≈ 0.25) and γ soft at low rotational frequencies. The highest experimentally observed positive-parity state in 65Ga (41/2+) is in good agreement with the calculated crossing of the collective band with a non-collective one terminating at this spin.
Received: 20 December 2000 / Accepted: 2 May 2001 相似文献
9.
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
10.
J.H. Hamilton A.V. Ramayya J.K. Hwang X.Y. Luo J.O. Rasmussen E.F. Jones X.Q. Zhang S.J. Zhu P.M. Gore T.N. Ginter I.Y. Lee R.V.F. Janssens I. Ahmed J.D. Cole W. Greiner G. Ter-Akopian Yu. Oganessian 《The European Physical Journal A - Hadrons and Nuclei》2002,15(1-2):175-179
With new high statistic data, new isotopes and new high-spin structures are observed in neutron-rich nuclei populated in the
spontaneous fission of 252Cf. The 135Te levels are extended, and many new levels in 139,141Ba observed. The coexistence of collective and single particle-hole states is found in 135Te. The N = 83 135Te and 139Ba show marked differences associated with differences in their particle and hole states. New levels in 141Ba complete evidence for two opposite-parity doublets characteristic of stable octupole deformation. In 114,116Pd a second backbend is observed for the first time in this mass region and the backbend in 118Pd occurs earlier than in 112-116Pd because of a reduction in pairing. Gamma-type vibrational bands are seen up to 13+ to 15+ in 104,106Mo, 108-112Ru, and 112-116Pd. Their behavior reflects prolate to triaxial shapes in these nuclei. The levels of 162,164Gd are observed for the first time. As N increases toward mid-shell at 104, the moments of inertia in N = 100 164Gd show an unexpected decrease compared to N = 98 162Gd. The levels in 162,164Gd form remarkable shifted identical bands with nuclei separated by 2n, 2p, α, and 2α.
Received: 21 March 2002 / Accepted: 16 May 2002 / Published online: 31 October 2002
RID="a"
ID="a"e-mail: j.h.hamilton@vanderbilt.edu 相似文献
11.
Krishichayan A. Chakraborty S. Mukhopadhyay S. Ray N. S. Pattabiraman S. S. Ghugre R. Goswami A. K. Sinha S. Sarkar U. Garg P. V. Madhusudhana Rao S. K. Basu B. K. Yogi L. Chaturvedi A. Dhal R. K. Sinha M. Saha Sarkar S. Saha R. Singh R. K. Bhowmik A. Jhingan N. Madhavan S. Muralithar S. Nath R. P. Singh P. Sugathan 《The European Physical Journal A - Hadrons and Nuclei》2006,29(2):151-159
Yrast and near-yrast energy levels in the neutron-rich N ∼ 20 nuclei 34P, 36S were populated using transfer/deep-inelastic processes following the 34S + 115In reaction at an incident energy of 140MeV. The use of a multi-clover array has facilitated polarization measurements of
the observed γ-rays and necessitated some changes in the previously known level scheme. The observation of the negative-parity
levels in these nuclei on the periphery of the “island of inversion” is indicative of the influence of the intruder orbitals
on the level structure at low spins. Shell-model calculations indicate that the inclusion of the orbitals from the upper pf shell is important even for the low-lying positive-parity states. 相似文献
12.
Some of the low-lying states in many isotopes144Nd,148Sm,152Gd and156Gd show a similar typical behaviour. The first 2+ is regarded as a single quadrupole phonon state and 3− as a single octupole phonon state. The levels with the spins and parities 1−, 5−, 3−, 4−, etc. are considered due to the simultaneous excitation of quadrupole and octupole phonons. If this consideration is correct,
then the transition fromJ
− to 2+ states must contain an appreciableE3 content. Theβ-γ-γ angular correlation coefficients for the cascade ofβ-rays ofE
max 800 keV→γ-rays of 1489 keV→γ-rays of 696 keV are used to estimateE3 content inE1 transition in144Nd. 相似文献
13.
14.
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
15.
Vinod Kumar Pragya Das R.P. Singh S. Muralithar R.K. Bhowmik 《The European Physical Journal A - Hadrons and Nuclei》2003,17(2):153-157
The fusion evaporation reaction 122Sn(14N, 4n)132La was used to populate the high-spin states of 132La at the beam energy of 60 MeV. A new band consisting of mostly E2 transitions has been discovered. This band has the interesting links to the ground state 2- and the isomeric state 6-. A new transition of energy 351 keV connecting the low-spin states of the positive-parity band based on the πh
11/2 ⊗ νh
11/2 particle configuration, has been found. This has played a very important role in resolving the existing ambiguities and inconsistencies
in the spin assignment of the band head.
Received: 12 August 2002 / Accepted: 18 March 2003 / Published online: 7 May 2003 相似文献
16.
Kuljeet Singh Z. Naik R. Kumar J. Goswamy D. Mehta N. Singh C. R. Praharaj E. S. Paul K. P. Singh R. P. Singh S. Muralithar N. Madhavan J. J. Das S. Nath A. Jhingan P. Sugathan R. K. Bhowmik 《The European Physical Journal A - Hadrons and Nuclei》2005,25(3):345-354
High-spin states in 123Cs, populated via the 100Mo ( 28Si, p4n) fusion-evaporation reaction at E
lab = 130 MeV, have been investigated employing in-beam γ-ray spectroscopic techniques. Rotational bands, built on πg
7/2, πg
9/2 and the unique-parity πh
11/2 orbitals, have been extended and evolve into bands involving rotationally aligned ν(h
11/2)2 and π(h
11/2)2 quasiparticles. A three-quasiparticle band based on the high-K πh
11/2 ⊗ νg
7/2 ⊗ νh
11/2 configuration has also been observed. Total Routhian Surface (TRS) calculations have been used to predict the nuclear shape
parameters ( β2, β4, γ) for the various assigned configurations. The assigned configurations have been discussed in the framework of a microscopic
theory based on the deformed Hartree-Fock (HF) and angular-momentum projection techniques. 相似文献
17.
18.
R.A. Radhi 《The European Physical Journal A - Hadrons and Nuclei》2003,16(3):387-392
Electron scattering Coulomb form factors for the single-particle quadrupole transitions in p-shell and sd-shell nuclei have been studied. Core polarization effects are included through a microscopic theory that includes excitations
from the core orbits up to higher orbits with 2ω excitations. The modified surface delta interaction is adopted as a residual
interaction. The results are discussed for the ( 1p
1/2
-1↦1p
3/2
-1) proton transition in 15N, ( 1d
5/2↦2s
1/2) neutron transition in 17O and ( 1d
3/2
-1↦2s
1/2
-1) proton transition in 39K. The inclusion of core polarization effects modifies the form factors markedly and describes the experimental data very
well in both the absolute strength and the momentum transfer dependence.
Received: 18 April 2002 / Accepted: 1 July 2002 / Published online: 6 March 2003
RID="a"
ID="a"e-mail: baguniv@uruklink.net
Communicated by A. Molinari 相似文献
19.
Ts. Venkova M. -G. Porquet A. Astier I. Deloncle P. Petkov A. Prévost F. Azaiez A. Bogachev A. Buta D. Curien O. Dorvaux G. Duchêne J. Durell B. J. P. Gall M. Houry F. Khalfallah R. Lucas M. Meyer I. Piqueras N. Redon A. Roach M. Rousseau O. Stézowski Ch. Theisen 《The European Physical Journal A - Hadrons and Nuclei》2005,26(3):315-319
High-spin states of the N = 87 nuclei, 147Nd and 145Ce, have been populated in the 12C + 238U and 18O + 208Pb fusion-fission reactions at 90 MeV and 85 MeV bombarding energy, respectively. The emitted γ-radiation was detected using
the Euroball III and IV arrays. High-spin states of the 147Nd isotope have been identified for the first time. The high-spin yrast and near-to-yrast structures of the 145Ce nucleus have been considerably extended. The newly observed structures, discussed by analogy with the neighbouring isotones,
show the coupling of an h9/2 neutron to the quadrupole and octupole excitations of the core. 相似文献
20.
M. Lach J. Styczeń W. Meczyński P. Bednarczyk A. Bracco J. Grebosz A. Maj J.C. Merdinger N. Schulz M.B. Smith K.M. Spohr J.P. Vivien M. Ziebliński 《The European Physical Journal A - Hadrons and Nuclei》2003,16(3):309-311
High-spin states of the 42Ca nucleus, populated in the 68 MeV 18O + 30Si reaction, have been studied in a γ-γ-recoil coincidence experiment. The level scheme of 42Ca has been extended up to 13.7 MeV. An elaborate decay pattern with various paths, together with high-quality DCO and polarization
information assigns spins and parities for almost all observed levels. The sequence of non-yrast positive-parity states is
discussed and compared with highly deformed bands in 36Ar and 40Ca.
Received: 26 November 2002 / Accepted: 11 December 2002 / Published online: 18 February 2003
RID="a"
ID="a"e-mail: Malgorzata.Lach@ifj.edu.pl
RID="b"
ID="b"Present address: TRIUMF, Vancouver, Canada.
RID="†"
ID="†"Deceased.
Communicated by D. Schwalm 相似文献