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1.
Lalazissis G. A. Vretenar D. Ring P. 《The European Physical Journal A - Hadrons and Nuclei》2004,22(1):37-45
The Relativistic Hartree-Bogoliubov model is applied in the analysis of ground-state properties of Be, B, C, N, F, Ne and Na isotopes. The model uses the NL3 effective interaction in the mean-field Lagrangian, and describes pairing correlations by the pairing part of the finite-range Gogny interaction D1S. Neutron separation energies, quadrupole deformations, nuclear matter radii, and differences in radii of proton and neutron distributions are compared with recent experimental data.Received: 27 August 2003, Revised: 12 March 2004, Published online: 19 October 2004PACS:
21.60.Jz Hartree-Fock and random-phase approximations - 21.10.Gv Mass and neutron distributions - 27.20. + n
- 27.30. + t
相似文献
2.
Variation-after-projection (VAP) calculations in conjunction with the Hartree- Bogoliubov (HB) ansatz have been carried out for A = 68-88, N = Z nuclei. In this framework, the yrast spectra with
, B(E2) transition probabilities and deformation parameter (
) have been obtained. A pairing interaction for like particles as well as protons and neutrons has been included in the model for a two-body interaction.Received: 28 April 2003, Revised: 20 March 2004, Published online: 14 September 2004PACS:
21.10.-k Properties of nuclei; nuclear energy levels - 21.60.-n Nuclear structure models and methods - 27.50. + e
相似文献
3.
We have used a self-consistent version of the BCS + RQRPA method for a systematic study of the two-neutrino double-beta-decay of nuclei with
. The comparison with other approaches, namely the QRPA and the RQRPA, shows that inclusion of the quasiparticle correlations at the BCS level reduces the ground-state correlations in the particle-particle channel of the proton-neutron interaction. This in turn results in a systematic reduction of the double-beta-decay matrix elements. The effect of the extension of the formalism on the Ikeda sum rule has been discussed.Received: 28 July 2003, Published online: 5 February 2004PACS:
21.60.Jz Hartree-Fock and random-phase approximations - 23.40.Bw Weak-interaction and lepton (including neutrino) aspects - 23.40.Hc Relation with nuclear matrix elements and nuclear structure - 27.60. + j
相似文献
4.
A. N. Andreyev D. Ackermann S. Antalic H. J. Boardman P. Cagarda J. Gerl F. P. Heßberger S. Hofmann M. Huyse D. Karlgren A. Keenan H. Kettunen A. Kleinböhl B. Kindler I. Kojouharov A. Lavrentiev C. D. O’Leary M. Leino B. Lommel M. Matos C. J. Moore G. Münzenberg R. D. Page S. Reshitko S. Saro H. Schaffner C. Schlegel M. J. Taylor K. Van de Vel P. Van Duppen L. Weissman K. Heyde 《The European Physical Journal A - Hadrons and Nuclei》2003,18(1):39-54
Detailed fine-structure
-decay studies of 188,190Bi were performed using the complete-fusion reactions of 50,52Cr ions with a 142Nd target at the velocity filter SHIP. The evaporation residues were separated in-flight and subsequently identified on the basis of recoil-
, recoil-
-
/X-ray and excitation function measurements. Improved data on the
-decay of 188,190Bi were obtained and a number of new low-lying excited states in the daughters 184,186Tl were observed. An intruder, presumably 10- state was identified in 184Tl, extending the systematics of such states in the odd-odd Tl nuclei beyond the neutron mid-shell at N = 104. Some technical aspects of experiment at recoil separators are also discussed.Received: 14 March 2003, Revised: 1 May 2003, Published online: 2 September 2003PACS:
23.60.+e
decay - 27.70.+q
- 27.80.+w
C.D. OLeary: Present address: Department of Physics, University of York, York, UK.M.J. Taylor: Present address: Department of Physics and Astronomy, Rutgers Univesity, NJ, USA.L. Weissman: Present address: NSCL, Michigan State University, East Lansing, MI 48824-1321 USA.K. Heyde: Present address: EP-ISOLDE, CERN, CH-1211, Geneva 23, Switzerland. 相似文献
5.
S. Lalkovski A. Minkova M.-G. Porquet A. Bauchet I. Deloncle A. Astier N. Buforn L. Donadille O. Dorvaux B. P. J. Gall R. Lucas M. Meyer A. Prévost N. Redon N. Schulz O. Stézowski 《The European Physical Journal A - Hadrons and Nuclei》2003,18(4):589-596
High-spin states in 108,110Pd isotopes are studied by
-ray spectroscopy of heavy-ion-induced fission. The Pd isotopes are produced in the fission channel of the 31P + 176Yb reaction at beam energy 152 MeV. The prompt
-rays are detected with the EUROBALL4 multidetector array. The yrast states of 108,110Pd have been observed above the region of the first backbend. The level scheme of 108Pd was extended with a new negative-parity band. The yrast sequence in 110Pd is observed up to spin I = 14 + and negative-parity bands have also been identified. The backbending in these even-mass Pd isotopes is associated with the alignment of the neutron (h
11/2)2 pair. The negative-parity states arise from two neutron configurations
and
and they are interpreted in the frame of two-quasiparticle + rotor model as semidecoupled bands. The observed experimental staggering in the
-bands of 108,110Pd supports the theoretical predictions for
-instability of their shapes.Received: 22 April 2003, Revised: 27 June 2003, Published online: 2 December 2003PACS:
21.60.-n Nuclear structure models and methods - 23.20.Lv
transitions and level energies - 25.70.Jj Fusion and fusion-fission reactions - 27.60. + j
相似文献
6.
C. Y. Xie X. H. Zhou Y. Zheng Y. H. Zhang Z. Liu Z. G. Gan T. Hayakawa M. Oshima T. Toh T. Shizuma J. Katakura Y. Hatsukawa M. Matsuda H. Kusakari M. Sugawara K. Furuno T. Komatsubara 《The European Physical Journal A - Hadrons and Nuclei》2004,19(1):7-9
The level structure of the doubly odd nucleus 146Tb has been studied via the 118Sn(32S, 1p3n) reaction using techniques of in-beam
-ray spectroscopy. Measurements of
-ray anisotropies, X-
and
-
-t coincidences were performed with 12 BGO(AC)HPGe detectors. Based on the measured results, the level scheme of 146Tb has been revised significantly and extended up to an excitation energy of 8.39 MeV. The level structure has been interpreted qualitatively by coupling an h
11/2 proton-particle and an h
11/2 neutron-hole to the excited states in the 146Gd core.Received: 3 July 2003, Published online: 26 November 2003PACS:
23.20.Lv
transitions and level energies - 27.60. + j
相似文献
7.
8.
X. Z. Cai C. Zhong W. Q. Shen Y. G. Ma H. Y. Zhang Y. B. Wei J. G. Chen W. Guo K. Wang G. L. Ma X. F. Zhou 《The European Physical Journal A - Hadrons and Nuclei》2004,20(2):263-267
,
and
have been calculated via the BUU model with soft EOS and 0.8 times of
. The density distribution without any adjustable parameters which comes from the RMF model has been introduced into the BUU calculation to replace the normally used one-parameter square-type distribution. The calculated results can reproduce the experimental data well for both halo- and stable-nuclei-induced reactions. Here
or
is calculated as the difference between
of halo nucleus and core nucleus, by assuming
. It indicates that this assumption works very well at high energy in the BUU calculation. More experimental measurements are necessary to test the validity of this assumption at intermediate energy.Received: 12 June 2003, Revised: 29 September 2003, Published online: 27 April 2004PACS:
24.10.-i Nuclear reaction models and methods - 25.60.Dz Interaction and reaction cross-sections - 25.60.Gc Breakup and momentum distributions - 27.20. + n
相似文献
9.
H. Röpke 《The European Physical Journal A - Hadrons and Nuclei》2004,22(2):213-230
The low-lying rotational bands of A = 36-48 nuclei are consistently explained by starting from the recently discovered, superdeformed intrinsic state of 36Ar as the core, filling successively the first three Nilsson orbits above the Fermi border. The critical single-particle energies were obtained from experimental data as were the residual interactions in the parametrization of Brink and Kerman. Implicit are the rearrangement energies due to configuration-dependent equilibrium deformations. The binding energies of 20 experimental bandheads were used to derive the parameters while another 38 bandheads were subsequently predicted and identified almost completely. The Racavy expression reduced by 20% reproduces or predicts the values of the deformation parameter
. The empirical Nilsson model amended by
-vibrational and rotation-aligned bands accounts completely for the multi-particle excitations from the N = 2 into the N = 3 major shell which are not accessible by shell-model calculations. In the case of 40Ca a spectrum of 42 states below E
x
= 8 MeV is explained.PACS:
21.60.Ev Collective models - 21.10.Dr Binding energies and masses - 27.30. + t
- 27.40. + z
相似文献
10.
P. Kowina M. Wolke H. -H. Adam A. Budzanowski R. Czyżykiewicz D. Grzonka J. Haidenbauer M. Janusz L. Jarczyk A. Khoukaz K. Kilian P. Moskal W. Oelert C. Piskor-Ignatowicz J. Przerwa C. Quentmeier T. Rożek R. Santo G. Schepers T. Sefzick M. Siemaszko J. Smyrski S. Steltenkamp A. Strzałkowski P. Winter P. Wüstner W. Zipper 《The European Physical Journal A - Hadrons and Nuclei》2004,22(2):293-299
The production of the
- and
-hyperons has been measured via the
reaction at the internal COSY-11 facility in the excess energy range between 14 and 60 MeV. The transition of the
cross-section ratio from about 28 at
MeV to the high-energy level of about 2.5 is covered by the data showing a strong decrease of the ratio between 10 and 20 MeV excess energy. Effects from the final-state interactions in the p-
channel seem to be much smaller than in the p-
channel. Estimates of the effective range parameters are given for the
and the
systems.PACS:
13.75.-n Hadron-induced low- and intermediate-energy reactions and scattering (energy
GeV) - 13.75.Ev Hyperon-nucleon interactions - 13.85.Lg Total cross-sections - 25.40.Ep Inelastic proton scattering 相似文献
11.
R. M. Lieder A. A. Pasternak E. O. Podsvirova A. D. Efimov V. M. Mikhajlov R. Wyss Ts Venkova W. Gast H. M. Jäger L. Mihailescu D. Bazzacco S. Lunardi R. Menegazzo C. Rossi Alvarez G. de Angelis D. R. Napoli T. Rzaca-Urban W. Urban A. Dewald 《The European Physical Journal A - Hadrons and Nuclei》2004,21(1):37-55
For a level scheme investigation of 144Gd an experiment with the
-spectrometer EUROBALL III has been carried out and lifetimes have been measured with the
-spectrometer GASP using the Doppler-shift attenuation method. The high-spin states have been populated in these experiments by means of the 100Mo(48Ti,4n) reaction at 215 MeV and the 114Cd(36S,6n) reaction at E = 182 MeV, respectively. The known quadrupole band has been modified and a new one has been established. Reduced E2 transition probabilities B(E2) were determined for seven members of these quadrupole bands. They show values between
and 130 W.u. and this considerable enhancement gives evidence for a significant nuclear deformation. A
configuration may be assigned to one of the quadrupole bands according to total Routhian surface calculations. The spin dependence of the B(E2) values has been explained by IBM calculations involving high-spin quasiparticle excitations.Received: 5 June 2003, Revised: 10 December 2003, Published online: 23 July 2004PACS:
21.10.Re Collective levels - 21.10.Tg Lifetimes - 21.60.Fw Models based on group theory - 27.60. + j
相似文献
12.
J. Kurpeta A. Plochocki A. N. Andreyev J. Äystö A. De Smet H. De Witte A.-H. Evensen V. Fedoseyev S. Franchoo M. Górska H. Grawe M. Huhta M. Huyse Z. Janas A. Jokinen M. Karny E. Kugler W. Kurcewicz U. Köster J. Lettry A. Nieminen K. Partes M. Ramdhane H. L. Ravn K. Rykaczewski J. Szerypo K. Van de Vel P. Van Duppen L. Weissman G. Walter A. Wöhr 《The European Physical Journal A - Hadrons and Nuclei》2003,18(1):31-37
A new high-spin isomer in 215Bi, with a half-life of 36.9(6) s, has been identified at the PSB-ISOLDE on-line mass separator using the pulsed-release technique combined with the element selective RILIS source. A decay scheme of
Bi was constructed and complemented with the low-spinstructure observed in
Bi decay. The population of a cascade on top of the
level in 215Poprovides evidence for Gamow-Teller
-decay of the high-spin 215Bi isomer.Received: 3 March 2003, Revised: 10 June 2003, Published online: 9 October 2003PACS:
23.20.Lv
transitions and level energies - 27.80.+w
- 29.30.Kv X- and
-ray spectroscopyV. Fedoseyev: Present address: ISOLDE, CERN-PPE, CH-1211, Geneva 23, Switzerland.M. Górska: Present address: GSI, Darmstadt, D-64220, Germany.M. Huhta: Present address: Nokia, Tampere, Finland. 相似文献
13.
The
-decay of 149Ba to 149La has been investigated by means of
- and X-ray spectroscopy, and a partial level scheme of 149La has been constructed for the first time. It includes thirteen
-rays and ten excited states. The exotic 149La is the heaviest lanthanum for which spectroscopic information is now available. We have applied the shell correction approach with the axially deformed Woods-Saxon potential in order to calculate the deformation energy for the 149La ground state. The deformed ground state was found at
0.23,
0 and
0.12.Received: 18 July 2003, Revised: 12 January 2004, Published online: 26 May 2004PACS:
27.60. + j
- 29.30.Kv X- and
-ray spectroscopy 相似文献
14.
T. Shizuma Z. G. Gan K. Ogawa H. Nakada M. Oshima Y. Toh T. Hayakawa Y. Hatsukawa M. Sugawara Y. Utsuno Z. Liu 《The European Physical Journal A - Hadrons and Nuclei》2004,20(2):207-210
Excited states in 136Ba, populated in deep inelastic collisions by the interaction of 450 MeV 82Se ions with a 139La target, have been studied by means of in-beam
-ray spectroscopy. A new isomer with
has been identified at an excitation energy Ex = 3.357 MeV. The half-life was determined as
ns. The extracted B(E2) value is much smaller than those in 132Te and 134Xe. This hindrance is investigated by a shell model calculation.Received: 22 September 2003, Revised: 11 November 2003, Published online: 6 April 2004PACS:
21.10.Tg Lifetimes - 23.20.Lv
transitions and level energies - 27.60. + j
相似文献
15.
Tohyama M. Takahara S. Schuck P. 《The European Physical Journal A - Hadrons and Nuclei》2004,21(2):217-225
We propose a time-independent method for finding a correlated ground state of an extended time-dependent Hartree-Fock theory, known as the time-dependent density matrix theory (TDDM). The correlated ground state is used to formulate the small amplitude limit of TDDM (STDDM) which is a version of extended RPA theories with ground-state correlations. To demonstrate the feasibility of the method, we calculate the ground state of 22
O and study the first 2 + state and its two-phonon states using STDDM.Received: 7 November 2003, Published online: 10 August 2004PACS:
21.10.Re Collective levels - 21.60.Jz Hartree-Fock and random-phase approximations - 27.30. + t
相似文献
16.
Ts Venkova R. M. Lieder W. Gast D. Bazzacco G. de Angelis E. Podsvirova H. M. Jäger L. Mihailescu R. Menegazzo S. Lunardi C. Rossi Alvarez C. Ur T. Martinez M. Axiotis D. Napoli W. Urban T. Rzaca-Urban S. Frauendorf 《The European Physical Journal A - Hadrons and Nuclei》2003,18(1):1-4
High-spin states in the odd-odd nucleus 172Lu have been populated in a 170Er(7Li, 5n) reaction and the emitted
-radiation was detected with the GASP array. Two sequences of a new identical band have been observed with the transition energies in the favoured and unfavoured sequences being identical within
keV at low spins and
keV at high spins over the whole observed spin range. Aninterpretation as a pseudo-spin singlet band of
configuration is proposed. It represents the best example of a pseudo-spin singlet band in normal deformed nuclei known until now.Received: 19 February 2003, Revised: 27 March 2003, Published online: 12 August 2003PACS:
21.10.-k Properties of nuclei; nuclear energy levels - 21.10.Re Collective levels - 23.20.Lv
transitions and level energies - 27.70.+q
相似文献
17.
18.
M. Stanoiu F. Azaiez F. Becker M. Belleguic C. Borcea C. Bourgeois B. A. Brown Z. Dlouhý Z. Dombrádi Z. Fülöp H. Grawe S. Grévy F. Ibrahim A. Kerek A. Krasznahorkay M. Lewitowicz S. Lukyanov H. van der Marel P. Mayet J. Mrázek S. Mandal D. Guillemaud-Mueller F. Negoita Y. E. Penionzhkevich Z. Podolyák P. Roussel-Chomaz M. G. Saint Laurent H. Savajols O. Sorlin G. Sletten D. Sohler J. Timár C. Timis A. Yamamoto 《The European Physical Journal A - Hadrons and Nuclei》2003,20(1):95-96
We have studied the structure of light neutron-rich nuclei around N = 16 by employing the in-beam
-ray spectroscopy technique using the fragmentation of secondary beams of 25,26Ne, 27,28Na and 29,30Mg isotopes. This secondary-beam cocktail was obtained by the fragmentation of a 36S beam at 77.5 MeV
by the SISSI/GANIL facility. By a second-step fragmentation, we have measured
-ray-residue coincidences in 17-20C and 23,24O and described the obtained levels in the framework of the shell model.Received: 31 October 2002, Published online: 24 February 2004PACS:
23.20.Lv
transitions and level energies - 21.60.Cs Shell model - 27.20. + n
- 27.30. + t
相似文献
19.
D. Sohler K. Lagergren J. Blomqvist B. Cederwall A. Johnson B. Hadinia L. Milechina J. Timár G. de Angelis P. Bednarczyk D. Curien A. Gadea J. Nyberg 《The European Physical Journal A - Hadrons and Nuclei》2004,19(2):169-172
The first experimental information about excited states in the N = Z + 1 nucleus 93Pd is presented. The experiment was performed using a 205 MeV 58Ni beam from the Vivitron accelerator at IReS, Strasbourg, impinging on a bismuth-backed 40Ca target. Gamma-rays, neutrons and charged particles emitted in the reactions were detected using the Ge detector array Euroball, the Neutron Wall liquid-scintillator array and the Euclides Si charged-particle detector system. The experimental level scheme is compared with the results of new shell model calculations which predict a coupling scheme with aligned neutron-proton pairs to greatly influence the level structure of
nuclei at low excitation energies.Received: 28 October 2003, Revised: 4 December 2003, Published online: 26 January 2004PACS:
21.10.Hw Spin, parity, and isobaric spin - 23.20.Lv
transitions and level energies - 27.60. + j
- 21.60.Cs Shell model 相似文献
20.
M. Stanoiu M. Belleguic Zs. Dombrádi D. Sohler F. Azaiez B. A. Brown M. J. Lopez-Jimenez M. G. Saint-Laurent O. Sorlin Yu.-E Penionzhkevich N. L. Achouri J. C. Angélique C. Borcea C. Bourgeois J. M. Daugas F. De Oliveira-Santos Z. Dlouhy C. Donzaud J. Duprat S. Grévy D. Guillemaud-Mueller S. Leenhardt M. Lewitowicz S. M. Lukyanov W. Mittig M. G. Porquet F. Pougheon P. Roussel-Chomaz H. Savajols Y. Sobolev C. Stodel J. Timár 《The European Physical Journal A - Hadrons and Nuclei》2004,22(1):5-8
The structure of the A/Z = 3 nucleus 15B has been investigated using the in-beam
-spectroscopy technique with a fragmentation reaction of a 36S beam on a 9Be target at 77.5
. The fragments were identified and selected by their energy loss and time of flight using the SPEG spectrograph.
-ray energies and intensities have been measured in coincidence with the projectile-like fragments. From this information as well as from the
-coincidence relationships a level scheme is proposed for 15B up to the neutron separation energy. The experimental results have been interpreted using shell model calculations in the psd valence space. Effects of the weakly bound nature of the valence neutrons have been observed.Received: 4 May 2004, Revised: 2 September 2004, Published online: 19 October 2004PACS:
25.70.Mn Projectile and target fragmentation - 23.20.Lv
transitions and level energies - 27.20. + n
- 21.60.Cs Shell model 相似文献