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1.
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
2.
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
3.
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
5.
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
6.
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
7.
Two experiments on the production of the a
0
+ (980)-resonance in the reaction
were performed with the ANKE spectrometer at COSY-Jülich. The decay channels
and
were measured simultaneously at energies T = 2.65 GeV and T = 2.83 GeV. For the reaction
a total production cross-section of
nb has been deduced for T = 2.65 GeV. Further goals of the data analysis are to determine differential cross-sections like angular distributions and the branching ratio
.Received: 30 September 2002, Published online: 22 October 2003PACS:
13.75.Cs Nucleon-nucleon interactions (including antinucleons, deuterons, etc.) - 25.40.Ve Other reactions above meson production thresholds (energies > 400 MeV)P. Fedorets: For the ANKE Collaboration: Complete collaboration list available via: http: //www.fz-juelich.de/ikp/ankeV. Kleber: For the ANKE Collaboration: Complete collaboration list available via: http: //www.fz-juelich.de/ikp/anke 相似文献
8.
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
9.
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
10.
Gyürky Gy. Fülöp Zs. Somorjai E. Kiss G. Rolfs C. 《The European Physical Journal A - Hadrons and Nuclei》2004,20(2):355-358
The absolute strengths of the
keV resonance in the
reaction and of the
keV resonance in the
reaction have been measured to
meV and
meV, respectively, in good agreement with previous values. These resonances can be used to measure the absolute acceptance of the recoil separator ERNA to a precision of about 10%.Received: 12 December 2003, Revised: 10 February 2004, Published online: 3 August 2004PACS:
24.30.-v Resonance reactions - 25.40.Lw Radiative capture - 26.20. + f Hydrostatic stellar nucleosynthesis 相似文献
11.
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
12.
P. Moskal H.-H. Adam A. Budzanowski R. Czyzykiewicz D. Grzonka M. Janusz L. Jarczyk B. Kamys A. Khoukaz K. Kilian P. Kowina T. Lister W. Oelert T. Rozek R. Santo G. Schepers T. Sefzick M. Siemaszko J. Smyrski S. Steltenkamp A. Strzalkowski P. Winter M. Wolke P. Wüstner W. Zipper 《The European Physical Journal A - Hadrons and Nuclei》2003,18(2-3):335-338
The production of
- and
-mesons in elementary nucleon-nucleon collisions has been investigated at the synchrotrons CELSIUS, COSY and SATURNE. The high-quality proton beam with low emittance and small momentum spread permits to study the creation of these mesons very close to the kinematical threshold, where --due to the rapid growth of the phase space volume-- the total cross-section increases by orders of magnitude over a few MeV range of the excess energy. The magnitude and energy dependence of the total cross-section as well as the occupation distribution of the phase space serve as observables for investigating the mechanisms underlying the production processes and the interaction of mesons with nucleons. The precise data on the
and
creation via the
reactions allowed to settle the general features of the
- and
-meson production and revealed the sensitivity of the mentioned observables to the nucleon-nucleon-meson final-state interaction. The particular production properties, like for example, the determination of the dominating exchange processes which lead to the excitation of the S
11 nucleon isobar in the case of
creation, must be established by confrontation with other observables. The present status of this investigation with an emphasis on the results of the COSY-11 Collaboration is briefly presented. The available data are interpreted in view of the production mechanism and the meson-nucleon interaction.Received: 30 September 2002, Published online: 22 October 2003PACS:
13.60.Le Meson production - 13.75.-n Hadron-induced low- and intermediate-energy reactions and scattering (energy
GeV) - 13.85.Lg Total cross sections - 25.40.-h Nucleon-induced reactions 相似文献
13.
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
14.
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
15.
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
16.
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
17.
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
18.
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
19.
The lifetimes of the 615 and 619 keV levels in 181Ta have been remeasured by using a
-
delayed coincidence set up with fast plastic (Pilot U) and BaF2 detectors. The presently measured values for both levels have been found to be in strong disagreement with results reported earlier. For the 615 keV level, the half-life has been found to be
ns in striking contrast to the earlier reported value of 17.6
s. The half-life of the 619 keV level has been found to be
ps, whereas values of 0.87 ns and 2.4 ns were reported previously. The nanosecond half-life of the 615 keV level has been confirmed from a separate measurement by employing a NaI(Tl)-Pilot U detector combination. The importance of lifetime measurements for the 615 keV level in perturbed angular correlation studies is discussed.Received: 17 December 2003, Revised: 19 April 2004, Published online: 19 October 2004PACS:
23.20.-g Electromagnetic transitions - 21.10.Tg Lifetimes 相似文献
20.
H. Rohdjeß F. Bauer J. Bisplinghoff K. Büßer M. Busch T. Colberg L. Demirörs C. Dahl P. D. Eversheim O. Eyser O. Felden R. Gebel J. Greiff F. Hinterberger E. Jonas H. Krause C. Lehmann J. Lindlein R. Maier A. Meinerzhagen C. Pauly D. Prasuhn D. Rosendaal P. von Rossen N. Schirm W. Scobel K. Ulbrich E. Weise T. Wolf R. Ziegler 《The European Physical Journal A - Hadrons and Nuclei》2003,18(2-3):555-558
At the Cooler-Synchrotron COSY/Jülich polarized and unpolarized elastic proton-proton scattering has been investigated with the EDDA-Experiment in the energy range (
-2.5 GeV). By taking scattering data during the acceleration of the beam with a large-acceptance (
-
) detector, precise excitation functions for differential cross-section and analyzing power have been measured in small energy steps with consistent normalization with respect to luminosity and polarization. These data have helped to improve the determination of phase-shifts at higher energies and impose tight quantitative upper bounds on possible resonant contributions to pp elastic scattering, as they might arise from exotic 6-quark configurations. Recently, with polarized beam and target, the spin-correlation parameters
,
, and
have been determined at 10 energies between 0.8 and 2.5 GeV. The observable
has been measured the first time above 800 MeV and our results are in sharp contrast to phase-shift predictions at higher energies.Received: 30 September 2002, Published online: 22 October 2003PACS:
24.70. + s Polarization phenomena in reactions - 25.40.Cm Elastic proton scattering - 11.80.Et Partial-wave analysis - 13.75.Cs Nucleon-nucleon interactions (including antinucleons, deuterons, etc.) 相似文献