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1.
A. N. Andreyev D. Ackermann F. P. Heßberger S. Hofmann M. Huyse I. Kojouharov B. Kindler B. Lommel G. Münzenberg R. D. Page K. Van de Vel P. Van Duppen K. Heyde 《The European Physical Journal A - Hadrons and Nuclei》2003,18(1):55-64
Alpha-decay of the new nuclide 184Bi has been studied in the complete-fusion reaction 93Nb(94Mo, 3n)184Bi at the velocity filter SHIP. The evaporation residues were separated in-flight and subsequently identified on the basis of recoil-
, recoil-
-
analysis and excitation functions measurements. Two
-decaying isomeric states in 184Bi with half-life values of 13(2) ms and 6.6(1.5) ms were identified. The
-branching ratio of 180Tl was deduced for the first time as
. Improved data on the fine-structure
-decay of 186Bi were obtained in the 93Nb(95Mo, 2n)186Bi reaction. A similarity of the decay energies and half-life values of 184,186Bi is pointed out and a possible explanation for this effect is suggested.Received: 14 March 2003, Revised: 29 April 2003, Published online: 2 September 2003PACS:
23.60.+e
decay - 27.70.+q
- 27.80.+w
K. Heyde: Present address: EP-ISOLDE, CERN, CH-1211, Geneva 23, Switzerland. 相似文献
2.
Exotic, neutron-rich proton-induced spallation products of 232Th and 238U obtained from the PS Booster ISOLDE facility have been investigated by
-
,
-
coincidence and spectrum-multiscaling measurements. A new method for the reduction of isobaric contamination enabled to study the unknown region beyond 208Pb for the decay chain A = 217. A new isotope 217Bi with a half-life of
s was discovered and its
-decay studied. For the first time, a half-life value of
s for the
-decay of 217Po was measured.Received: 3 March 2003, Revised: 13 May 2003, Published online: 30 September 2003PACS:
23.20.Lv
transitions and level energies - 23.60.+e
decay - 27.80.+w 190
A
219 - 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
3.
Isomeric states in 210-215Ra have been populated by the decay of the compound nuclei 216,220Ra produced in irradiations of 204,208Pb with 12C at
MeV. Published values for
-ray energies and half-lives were confirmed for
Ra. Our data for
Ra agree with the
-energies and the half-life measured at the RITU separator, University of Jyväskylä (Finland). Its decay pattern is complex. Two series of
-rays of
keV and
keV were observed. A half-life of
s was measured. The isomeric state is attributed to an 8 + state at E
* = 2053.8keV. A previously unknown isomeric state was assigned to
Ra. It has a half-life of (
)
and it decays by emission of
-rays with energies of 396.1keV and 802.0keV. It is attributed to a 13/2 + state at E
* = 1198.1 keV.PACS:
23.60. + e
decay - 27.90. + b
相似文献
4.
A folding potential describing the
-scattering on 16O over a broad energy range 25.8-146.0 MeV is constructed on the basis of
-like cluster and unclustered-nucleon configurations of 16O. The resulting potential does not need any renormalization to fit the angular distribution of elastic cross-sections. The effects of the repulsive part of
-
and
-nucleon interactions are investigated. The analysis suggests that both the
-
repulsive potential and the unclustered nucleonic configuration in the target are important to describe the scattering data over a broad range of incident energies. The root-mean-square radius for the 16O nucleus is deduced.Received: 5 December 2002, Published online: 9 October 2003PACS:
25.55.Ci Elastic and inelastic scattering - 24.10.Ht Optical and diffraction models - 21.60.Gx Cluster models 相似文献
5.
F. P. Heßberger S. Hofmann D. Ackermann P. Cagarda R. -D. Herzberg I. Kojouharov P. Kuusiniemi M. Leino R. Mann 《The European Physical Journal A - Hadrons and Nuclei》2004,22(3):417-427
The isotopes 251No and 253No were produced in nuclear reactions 206Pb(48Ca,3n)251No and 207Pb (48Ca,2n)253No. Radioactive decay of these isotopes and their daughter products has been investigated by means of
- and
-
- spectroscopy. An isomeric state 251m
No, having a half-life of
s and decaying by emission of
particles of
keV was identified. The measured decay data allowed for the construction of partial level schemes for 251No, 247,249Fm and 243,245Cf and an extrapolation of energy systematics of single particle levels of N = 145, 147 and 149 isotones with even Z towards higher atomic numbers up to Z = 102.PACS:
23.60. + e
decay - 27.90. + b
- 21.10.-k Properties of nuclei; nuclear energy levels 相似文献
6.
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
7.
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
8.
A short summary of the present status of prompt particle decays in the mass
region is presented. It includes recent results from a GAMMASPHERE experiment, which aimed at the combined high-resolution spectroscopy of light charged particles and
-rays to allow for more detailed studies of known decays and the identification of new cases of discrete prompt proton and
-particle emission from highly and superdeformed states.Received: 10 October 2002, Published online: 17 February 2004PACS:
23.50. + z Decay by proton emission - 23.60. + e
decay - 27.40. + z
- 27.50. + e
相似文献
9.
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
10.
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
11.
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 《The European Physical Journal A - Hadrons and Nuclei》2003,18(4):577-581
High-spin states in the odd-proton nucleus 173Lu have been populated in a 170Er(7Li,4n) reaction and the emitted
-radiation was detected with the GASP array. The favoured and unfavoured sequences of the
band have been considerably extended. The favoured sequence does not show any indication of a band crossing up to a rotational frequency of
0.45 MeV. This is the largest crossing frequency ever observed for 1/2- [541] bands of odd-proton nuclei with
and
. Previous Cranked Shell Model (CSM) calculations underestimate the crossing frequency by 100 keV.Received: 19 May 2003, Published online: 11 November 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
12.
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
13.
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
14.
We demonstrate the different effect of strange impurities (
and
) on the static properties of nuclei within the framework of the relativistic mean-field model. Systematic calculations show that the glue-like role of the
-hyperon is universal for all
-hypernuclei considered. However, the
-hyperon has a glue-like role only for the protons distribution in nuclei, while for the neutrons distribution it plays a repulsive role. On the other hand, the
-hyperon attracts the surrounding neutrons and reveals a repulsive force to the protons. Possible explanations of the above observation are discussed.Received: 10 March 2003, Revised: 6 November 2003, Published online: 5 May 2004PACS:
21.80. + a Hypernuclei - 24.10.Cn Many-body theory 相似文献
15.
J. G. Messchendorp 《The European Physical Journal A - Hadrons and Nuclei》2003,18(2-3):417-419
Preliminary differential cross-sections of the reactions
and
with A = 1
H, 12
C, and
nat
Pb are presented. A significant nuclear-mass dependence of the
invariant-mass distribution is found in the
channel. The dependence is not observed in the
channel. The in-medium observation in the
channel is consistent with an in-medium modification of the
interaction in the I = J = 0 channel, changing width and pole position of a
resonant state.Received: 30 September 2002, Published online: 22 October 2003PACS:
13.60.Le Meson production - 21.65. + f Nuclear matterJ.G. Messchendorp: For the TAPS and A2 Collaborations 相似文献
16.
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
17.
The effects of the open boundaries on the dynamical behavior of the optimal velocity traffic flow models with a delay time
allowing the car to reach its optimal velocity is studied using numerical simulations. The particles could enter the chain with a given injecting rate probability
, and could leave the system with a given extracting rate probability
. In the absence of the variation of the delay time
, it is found that the transition from unstable to metastable and from metastable to stable state occur under the effect of the probabilities rates
and
. However, for a fixed value of
, there exist a critical value of the extraction rate
above which the wave density disappears and the metastable state appears and a critical value
above which the metastable state disappears while the stable state appears.
and
depend on the values of
and the variation of the delay time
. Indeed
and
increase when increasing
and/or decreasing
. The flow of vehicles is calculated as a function of
,
and
for a fixed value of
. Phase diagrams in the (
) plane exhibits four different phases namely, unstable, metastable, stable. The transition line between stable phase and the unstable one is curved and it is of first order type. While the transition between stable (unstable) phase and the metastable phase are of second order type. The region of the metastable phase shrinks with increasing the variation of the delay time
and disappears completely above a critical value
.Received: 23 July 2003, Published online: 8 December 2003PACS:
05.50. + q Lattice theory and statistics (Ising, Potts, etc.) - 64.60.Cn Order-disorder transformations; statistical mechanics of model systems - 75.30.Kz Magnetic phase boundaries (including magnetic transitions, metamagnetism, etc.) - 82.20.Wt Computational modeling; simulation 相似文献
18.
A. Sibirtsev 《The European Physical Journal A - Hadrons and Nuclei》2003,18(2-3):475-478
We investigate the
decay width of excited charmonium states at finite nuclear density with simultaneous modification of both D- and
-mesons in nuclear matter. The strongest effect is found for the
-meson. The medium modification can be detected by dilepton spectroscopy as substantial
broadening and anomalous
absorption.Received: 30 September 2002, Published online: 22 October 2003PACS:
13.25.Gv Decays of
,
, and other quarkonia - 14.40.Lb Charmed mesons - 14.65.Dw Charmed quarks - 24.85. + p Quarks, gluons, and QCD in nuclei and nuclear processes 相似文献
19.
Yu Ts Oganessian A. V. Yeremin A. G. Popeko O. N. Malyshev A. V. Belozerov G. V. Buklanov M. L. Chelnokov V. I. Chepigin V. A. Gorshkov S. Hofmann M. G. Itkis A. P. Kabachenko B. Kindler G. Münzenberg R. N. Sagaidak Š Šáro H.-J. Schött B. Štreicher A. V. Shutov A. I. Svirikhin G. K. Vostokin 《The European Physical Journal A - Hadrons and Nuclei》2004,19(1):3-6
The upgraded separator VASSILISSA was used to confirm results of previous experiments on the synthesis of the heavy isotopes of the element 112 obtained in complete-fusion reactions of 48Ca and 238U. An additional reason was the non-observation of any events in the same reaction studied with the BGS separator at Berkeley. Limits of
for the atomic mass number of the observed spontaneously fissioning isotope were measured. The obtained results on the decay mode, half-life and production cross-section are in agreement with those obtained in our first experiment.Received: 10 June 2003, Revised: 29 July 2003, Published online: 2 December 2003PACS:
23.60. + e
decay - 25.70.-z Low and intermediate energy heavy-ion reactions - 25.85.Ca Spontaneous fission - 27.90. + b
相似文献