共查询到20条相似文献,搜索用时 15 毫秒
1.
F.P. Heßberger S. Hofmann I. Kojouharov D. Ackermann S. Antalic P. Cagarda B. Kindler B. Lommel R. Mann A.G. Popeko S. Saro J. Uusitalo A.V. Yeremin 《The European Physical Journal A - Hadrons and Nuclei》2002,15(3):335-342
The radioactive decay of 217Pa was investigated by means of α-γ-spectroscopy. Fine structure in the ground-state α-decay was established. Ambiguities
in the fine structure of the α-decay of the previously known isomeric state could be clarified by α-γ-coincidence measurements.
A previously unknown α-transition of E
α = (8306 ± 5) keV was detected and identified by means of delayed α-α- and α-γ-γ-coincidence measurements. A second isomeric
state decaying by α-emission was not observed. The quality of the previously reported data of the α-decay fine structure of
217Th was improved.
Received: 29 April 2002 / Accepted: 17 June 2002 / Published online: 19 November 2002
RID="a"
ID="a"e-mail: f.p.hessberger@gsi.de
Communicated by J. ?yst? 相似文献
2.
Y. Tagaya S. Hashimoto K. Morita Y.H. Pu T. Ariga K. Ohta T. Minemura I. Hisanaga T. Motobayashi T. Nomura 《The European Physical Journal A - Hadrons and Nuclei》1999,5(2):123-125
The α-decay energy and halflife of 195mAt were determined to be 6960±20 keV and 385+69
−51 ms respectively, on the basis of genetic correlations in the 169Tm(36Ar, α6n)195At reaction, while those of 195gAt measured simultaneously were 7105±30 keV and 146+21
−17 ms respectively, reconfirming the previously reported values. A new isotope 199Fr was also produced and identified in the same way in the 169Tm(36Ar, 6n)199Fr reaction, yielding Eα= 7655±40 keV and T1/2= 12+10
−4 ms.
Received: 26 March 1999 相似文献
3.
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
4.
H. Kettunen T. Enqvist M. Leino K. Eskola P.T. Greenlees K. Helariutta P. Jones R. Julin S. Juutinen H. Kankaanpää H. Koivisto P. Kuusiniemi M. Muikku P. Nieminen P. Rahkila J. Uusitalo 《The European Physical Journal A - Hadrons and Nuclei》2003,16(4):457-467
The low-energy nuclear structure and decay properties of the neutron-deficient isotopes 195At and 191Bi have been studied. 195At was produced in the reaction 142Nd(56Fe,p2n)195At and 191Bi as the daughter activity of 195At. The activities were implanted in a position-sensitive silicon detector after being separated from the primary beam by
a gas-filled recoil separator. The 1/2+ intruder state was determined to be the ground state in 195At with an alpha-decay energy of E
α = 6953(3) keV and a half-life T
1/2 = 328(20) ms. Another state with an alpha-decay energy E
α = 7075(4) keV and a half-life T
1/2 = 147(5) ms was found to decay to a 148.7(5) keV excited state in 191Bi for which a spin and parity of 7/2- were deduced. Consequently, the same 7/2- character was assigned to the initial state at 32(7) keV in 195At on the basis of unhindered alpha-decay. The 9/2- state, being the ground state in heavier odd-mass astatine isotopes, was not observed.
Received: 16 September 2002 / Accepted: 19 December 2002 / Published online: 25 March 2003
RID="a"
ID="a"e-mail: heikki.kettunen@phys.jyu.fi
RID="b"
ID="b"Present address: Laboratory of Radiochemistry, P.O. Box 55, FIN-00014, University of Helsinki, Finland.
RID="c"
ID="c"Present address: Radiation and Nuclear Safety Authority, P.O. Box 14, FIN-00881 Helsinki, Finland.
Communicated by W. Henning 相似文献
5.
J. Kurpeta A. Andreyev J. Äystö A.-H. Evensen M. Huhta M. Huyse A. Jokinen M. Karny E. Kugler J. Lettry A. Nieminen A. Płochocki M. Ramdhane H.L. Ravn K. Rykaczewski J. Szerypo P. Van Duppen G. Walter A. Wöhr 《The European Physical Journal A - Hadrons and Nuclei》2000,7(1):49-54
The decay of the neutron–rich isotope 216Bi, produced by proton–induced spallation at the PS Booster–ISOLDE facility, was investigated by β-γγ, αγ coincidence and
spectrum-multiscaling measurements. A new method for reducing isobaric contamination enabled to cover the unknown region “east”
of 208Pb for the isobaric chain A=216. The half-life of the β decay of 216Bi was found as T1/2= 135 ± 5 s. Its decay scheme was extended and the possible shell model configurations are proposed.
Received: 13 July 1999 / Revised version: 22 September 1999 相似文献
6.
A.N. Andreyev K. Van de Vel A. Barzakh A. De Smet H. De Witte D.V. Fedorov V.N. Fedoseyev S. Franchoo M. Górska M. Huyse Z. Janas U. Köster W. Kurcewicz J. Kurpeta V.I. Mishin K. Partes A. Plochocki P. Van Duppen L. Weissman 《The European Physical Journal A - Hadrons and Nuclei》2002,14(1):63-75
Alpha-decay properties of the neutron-deficient isotope 185Pb were studied at the PSB-ISOLDE (CERN) on-line mass separator using the resonance ionisation laser ion source (RILIS). The
nuclei of interest were produced in a 1.4 GeV proton-induced spallation reaction of a uranium graphite target. In contrast
to previous studies, two α-decaying isomeric states were identified in 185Pb. The relative production of the isomers, monitored by their α-counting rates, could be significantly changed when a narrow-bandwidth
laser at the RILIS setup was used to scan through the atomic hyperfine structure. Based on the atomic hyperfine structure
measurements, along with the systematics for heavier odd-mass lead isotopes, the spin and the parity of these states were
interpreted as 3/2- and 13/2+ and their nuclear magnetic moments were deduced. The α-decay energy and half-life value for the I
π = 13/2+ isomer are E
α = 6408(5) keV, T
1/2 = 4.3(2) s, respectively; while for the I
π = 3/2- isomer ( T
1/2 = 6.3(4) s) two α-decays with E
α1 = 6288(5) keV, I
α1 = 56(2)% and E
α2 = 6486(5) keV, I
α2 = 44(2)% were observed. By observing prompt α-γ coincidences new information on the low-lying states in the daughter isotope
181Hg was obtained.
Received: 7 February 2002 / Accepted: 19 February 2002 相似文献
7.
K. Jessen W. Andrejtscheff M. Bergström P. von Brentano A. Dewald B. Herskind H. Meise C. Schumacher G. Sletten O. Stuch D. Weißhaar I. Wiedenhöver J. Wrzesinski 《The European Physical Journal A - Hadrons and Nuclei》1999,4(1):9-10
A new high-spin isomer in 145Sm was observed by in-beam γ-ray spectroscopy with the reaction 122Sn(27Al,3np) at 127 MeV performed at the Nordball multi-detector array in Roskilde. The excitation energy of the isomer was determined
to be E
x= 11147 keV, and using the generalized centroid-shift method its half-life was found to be T
1/2= (7.4 ± 1.0) ns.
Received: 23 October 1998 相似文献
8.
P. Mohr 《The European Physical Journal A - Hadrons and Nuclei》2007,34(1):23-28
α-decay half-lives for 104, 105, 106Te and 108, 109, 110Xe close above the doubly-magic 100Sn are calculated from systematic double-folding potentials. The derived α preformation factors are compared to results for
212, 213, 214Po and 216, 217, 218Rn above the doubly-magic 208Pb. α-decay energies of Q
α = 5.42±0.07MeV and 4.65±0.15MeV are predicted for 104Te and 108Xe; the corresponding half-lives are T
1/2 ≈ 5ns for 104Te and of the order of 60μs for 108Xe. Additionally, the properties of rotational bands in 104Te are analyzed, and the first excited 2+ state in 104Te is predicted at E
x = 650±40keV; it decays preferentially by γ emission with a reduced transition strength of 10 Weisskopf units to the ground
state of 104Te and with a minor branch by α emission to the ground state of 100Sn. 相似文献
9.
J.C. Batchelder K.S. Toth C.R. Bingham L.T. Brown L.F. Conticchio C.N. Davids R.J. Irvine D. Seweryniak W.B. Walters J. Wauters E.F. Zganjar J.L. Wood C. DeCoster B. Decroix K. Heyde 《The European Physical Journal A - Hadrons and Nuclei》1999,5(1):49-52
The excitation energies of the single-particle normal and intruder levels in both 183Tl and 187Bi were measured for the first time via the α decay of 187Bi produced in the 97Mo(92Mo,pn)187Bi reaction. The previously unobserved 187Bi ground state (h9/2) to 183Tl ground state (s1/2) α transition was identified, establishing the 187Bi intruder state excitation energy to be 112(21) keV, 70 keV less than that of the same level in 189Bi.
Received: 10 September 1998 / Revised version: 18 December 1998 相似文献
10.
Ch. Miehé Ph. Dessagne Ch. Pujol G. Walter B. Jonson M. Lindroos 《The European Physical Journal A - Hadrons and Nuclei》1999,5(2):143-150
The β+– electron capture decay of 73Kr, produced at the ISOLDE CERN facility, has been studied by β-delayed proton and gamma emission. The established decay scheme
involves 15 up to now unreported gamma emitting levels in 73Br. The total proton branching ratio has been measured to be 0.0025 ± 0.0003. From this work, a spin and parity 3/2− is assigned to the 73Kr ground state, on the basis of the allowed β branch to the 73Br Jπ= 1/2− ground state and the feeding of the 5/2+ level located at 286 keV in 73Br.
Received: 17 September 1998 / Revised version: 25 January 1999 相似文献
11.
A.I. Levon J. de Boer M. Loewe M. Würkner T. Czosnyka J. Iwanicki P.J. Napiorkowski 《The European Physical Journal A - Hadrons and Nuclei》1998,2(1):9-11
The E1 transition from the 3/2− state to the ground state of 229Pa was identified in the (p,tγ) reaction. Its energy is found to be 11.6(3) keV. This leads to a value of Qg.s.=−4133(2) keV and to a mass defect of 229Pa of 29894(3) keV. It is concluded that the ground-state configuration of 229Pa is 3/2[651].
Received: 29 January 1998 相似文献
12.
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
13.
Yu.N. Lobach A.D. Efimov A.A. Pasternak 《The European Physical Journal A - Hadrons and Nuclei》1999,6(2):131-140
Lifetimes of excited states in 110Cd have been measured by the Doppler shift attenuation method in the reaction (α,2nγ) at E
α= 25 MeV. Lifetime values for 8 states and lifetime limits for 3 states were obtained. The band structures of 110Cd have been interpreted in terms of a modified version of the interacting boson model (IBM + 2 q.p.). The calculations explain
well the excitation energies and electromagnetic transition probabilities up to J
π= 16+, except for the 10+
1 state. The structural features are discussed in terms of collective and two quasiparticle excitations.
Received: 20 March 1999 / Revised version: 28 May 1999 相似文献
14.
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
15.
B. Fornal R. Broda W. Królas T. Pawłat J. Wrzesiński P.J. Daly P. Bhattacharyya Z.W. Grabowski C.T. Zhang D. Bazzacco S. Lunardi C. Rossi Alvarez G. de Angelis D.R. Napoli 《The European Physical Journal A - Hadrons and Nuclei》1998,1(4):355-357
Prompt and delayed γ-rays in nuclei of the 208Pb region produced in 450 MeV 76Ge +208Pb collisions have been studied at GASP. Yrast states above the α-decaying isomer in 211Po have been located including a 0.25 μs 31/2− isomer at 2135 keV and a 2 μs isomer at 4874 keV.
Received: 22 September 1997 相似文献
16.
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
17.
J.H. Ha J.C. Kim C.S. Lee J.Y. Huh C.-B. Moon Y. Gono S. Mitarai T. Morikawa M. Shibata H. Watanabe M. Miyake E. Komatsu A. Odahara E. Ideguchi X.H. Zhou 《The European Physical Journal A - Hadrons and Nuclei》1998,1(3):247-248
High-spin states of odd-odd 168Lu were observed up to 18ħ for the first time using the 159Tb(13C, 4nγ)168Lu reaction at E
13C= 58.5 MeV. γ-γ coincidence, E
γ singles, excitation function, and the DCO ratios were measured. Two rotational bands with signature splitting were populated,
among which the lower-energy band is identified as π 7/2+[404] ⊗ν 5/2+[642] in view of alignment and energy systematics.
Received: 27 October 1997 相似文献
18.
S. Kamerdzhiev J. Speth G. Tertychny 《The European Physical Journal A - Hadrons and Nuclei》2000,7(4):483-490
Recent experimental studies of the giant electric resonance region in 58Ni and 40Ca with inelastically scattered α-particles of energy Eα= 240 MeV are analyzed within a microscopic nuclear structure model.
The model includes the continuum RPA and more complex 1p1h⊗phonon configurations. By superimposing the contributions of different
multipoles up to L = 4 we obtain good agreement with the newest (reanalyzed) data for the isoscalar monopole strength and
for the total (α,α′) cross section in 58Ni. Agreement with experiment for the isoscalar monopole resonance in 40Ca is obtained too. We emphasize the necessity of using microscopic transition densities and discuss consequences for the
analyses of such experiments in light and medium mass nuclei. It is shown that the gross structure of the isoscalar monopole
resonance in 40Ca is caused by the 1p1h⊗phonon configurations.
Received: 23 December 1999 / Revised version: 28 February 2000 相似文献
19.
H. Röpke J. Brenneisen M. Lickert 《The European Physical Journal A - Hadrons and Nuclei》2002,14(2):159-167
Eight high-spin states in 36Ar below 10MeV excitation energy, among them a prospective J
π = 8- state at 9408keV and the J? 8 levels of the recently discovered superdeformed rotational band, have been observed by n-γ coincidence measurements with
the 33S(α, nγ) reaction at E
α = 14.4 and 13.4MeV. High-spin assignments of, respectively, J
π = 6+ and 5- were obtained for the E
p = 1209 and 1462keV (E
x = 9682 and 9927keV) resonances of the 35Cl (p,γ) reaction by a measurement of γ-ray angular distributions. The spectrum of the high-spin and of the E
x? 7.4MeV levels is decomposed according to the underlying shell model configurations with n = 0, 1, 2, 4 particles excited from the N = 2 into the N = 3 major shell. The role of four-particle excitations, all connected with large prolate distortions, is elucidated for the
entire A = 36-40 mass region.
Received: 21 December 2001 / Accepted: 25 March 2002 相似文献
20.
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