共查询到20条相似文献,搜索用时 46 毫秒
1.
T. Spillane F. Raiola F. Zeng H. W. Becker L. Gialanella K. U. Kettner R. Kunze C. Rolfs M. Romano D. Schürmann F. Strieder 《The European Physical Journal A - Hadrons and Nuclei》2007,31(2):203-205
For the β--decay of 198Au in a Au metallic environment the half-life was observed to be longer by 0.4±0.7% at room temperature (T = 293K) and by 4.0±0.7% when the metal was cooled to T = 12K, both compared to the literature value of T
1/2 = 2.6943±0.0008d. 相似文献
2.
B. Limata F. Raiola B. Wang S. Yan H. W. Becker A. D'Onofrio L. Gialanella V. Roca C. Rolfs M. Romano D. Schürmann F. Strieder F. Terrasi 《The European Physical Journal A - Hadrons and Nuclei》2006,28(2):251-252
For the β+-decay of 22Na in the metallic environment Pd cooled to T = 12 K the 22Na half-life was observed to be shorter by 1.2±0.2%. The result is consistent with --but lower than-- the prediction of the
Debye plasma model. 相似文献
3.
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
4.
D. Rudolph R. Hoischen M. Hellström S. Pietri Zs. Podolyák P. H. Regan A. B. Garnsworthy S. J. Steer F. Becker P. Bednarczyk L. Cáceres P. Doornenbal J. Gerl M. Górska J. Grebosz I. Kojouharov N. Kurz W. Prokopowicz H. Schaffner H. J. Wollersheim L. -L. Andersson L. Atanasova D. L. Balabanski M. A. Bentley A. Blazhev C. Brandau J. R. Brown C. Fahlander E. K. Johansson A. Jungclaus 《The European Physical Journal A - Hadrons and Nuclei》2008,36(2):131-138
The fragmentation of a 550MeV/u primary beam of 58Ni on a 9Be target has been used to measure time- and energy-correlated γ decays following the implantation of event-by-event discriminated
secondary fragments into a 9Be stopper plate. A new isomeric γ decay with T
1/2 = 14(
) ns and E
γ = 646.2(2) keV is observed and attributed to the decay of the yrast 3/2- state in 53
27Co26 . This short-lived isomeric state has been populated by means of nuclear reactions during the stopping process of the secondary
fragments. The experimental findings are discussed in the framework of large-scale spherical shell model calculations in conjunction
with isospin symmetry-breaking residual interactions for the A = 53 , T
z = ±1/2 mirror nuclei 53Co and 53Fe . 相似文献
5.
J. Khuyagbaatar S. Hofmann F. P. Heßberger D. Ackermann S. Antalic H. G. Burkhard S. Heinz B. Kindler A. F. Lisetskiy B. Lommel R. Mann K. Nishio H. J. Schött B. Sulignano 《The European Physical Journal A - Hadrons and Nuclei》2007,34(4):355-361
Isomeric states in 214Th and 213Th were identified by means of γ -rays measured in delayed coincidence with the implanted evaporation residues. These were
produced in irradiations of 164Dy with 54Cr projectiles and separated in-flight by the velocity filter SHIP. An isomeric state of I
π = 8+ with a half-life of (1.24±0.12) μs was identified in 214Th . The configuration π[1h
9/2 ⊗ 2f
7/2] was assigned to this state. An isomeric state with a half-life of (1.4±0.4) μs was observed in 213Th . Tentatively it was assigned to an I
π = 13/2+ state. 相似文献
6.
Yu. B. Gurov B. A. Chernyshev S. V. Isakov V. S. Karpukhin S. V. Lapushkin I. V. Laukhin V. A. Pechkurov N. O. Poroshin V. G. Sandukovsky 《The European Physical Journal A - Hadrons and Nuclei》2007,32(3):261-266
Experimental search for superheavy hydrogen isotopes 6H and 7H was performed in the stopped pion absorption on 9Be and 11B nuclei. The structures in the missing-mass spectra were observed in the reaction channels 9Be(π-, pd )X and 11B(π-, p4He)X . Four states of 6H were proposed. Evidences for 7H formation were obtained in the reaction channels 9Be(π-, pp)X and 11B(π-, p3He)X . 相似文献
7.
T. Rzaca-Urban W. Urban M. Saha Sarkar S. Sarkar J. L. Durell A. G. Smith B. J. Varley I. Ahmad 《The European Physical Journal A - Hadrons and Nuclei》2007,32(1):5-9
The Penning trap mass spectrometer JYFLTRAP, coupled to the Ion Guide Isotope Separator On-Line (IGISOL) facility at Jyv?skyl?,
was employed to measure the atomic masses of neutron-rich 70-73Ni and 73, 75Cu isotopes with a typical accuracy less than 5keV. The mass of 73Ni was measured for the first time. Comparisons with the previous data are discussed. Two-neutron separation energies show
a weak subshell closure at 68
28Ni40 . A well established proton shell gap is observed at Z = 28 . 相似文献
8.
L. Gialanella F. Strieder L. Campajola A. D'Onofrio U. Greife G. Gyurky G. Imbriani G. Oliviero A. Ordine V. Roca C. Rolfs M. Romano D. Rogalla C. Sabbarese E. Somorjai F. Terrasi H.P. Trautvetter 《The European Physical Journal A - Hadrons and Nuclei》2000,9(3):303-305
The absolute cross section σ (E) of the radiative capture reaction p(7Be,γ)8B at the center-of-mass energy E = 992 keV has been measured using a radioactive 7Be ion beam and a windowless gas target system filled with H2 gas. The 8B residual nuclides were detected with a recoil separator consisting of momentum and velocity filters and a ΔE-E detector
telescope. The 8B yield was observed concurrently with the 7Be + p elastic scattering yield, relating σ(E) to the Rutherford scattering cross section. The resulting value, σ(E) = 0.41
± 0.11 μb, leads to an S(E) factor at zero energy of S(0) = 16 ± 4 eV b, in fair agreement with recommended values.
Received: 8 February 2000 相似文献
9.
J. Huikari M. Oinonen A. Algora J. Cederkäll S. Courtin P. Dessagne L. Fraile S. Franchoo H. Fynbo W.X. Huang A. Jokinen A. Knipper F. Marechal C. Miehé E. Nacher K. Peräjärvi E. Poirier L. Weissman J. Äystö 《The European Physical Journal A - Hadrons and Nuclei》2003,16(3):359-363
The β-decay of 75Sr to its mirror nucleus 75Rb was studied at the ISOLDE PSB facility at CERN by means of β-delayed γ and proton spectroscopy. The decay Q-value and β-delayed γ intensity were measured for the first time. These results, 10.60±0.22 MeV and 4.5+1.9
-0.7%, together with accurate measurements of the β-decay half-life and β-delayed proton branching ratio yielded the Gamow-Teller
strength 0.35±0.05 for the mirror transition. Implications of the results on studies of deformation effects and on the path
of the rapid proton capture process are discussed.
Received: 26 September 2002 / Accepted: 30 October 2002 / Published online: 18 February 2003
RID="a"
ID="a"e-mail: jussi.huikari@phys.jyu.lfi
Communicated by D. Schwalm 相似文献
10.
A. Kankainen G. K. Vorobjev S. A. Eliseev W. Huang J. Huikari A. Jokinen A. Nieminen Yu. N. Novikov H. Penttilä A. V. Popov S. Rinta-Antila H. Schatz D. M. Seliverstov Yu. P. Suslov J. Äystö 《The European Physical Journal A - Hadrons and Nuclei》2005,25(3):355-363
Decay properties of neutron-deficient exotic nuclei close to A=80 have been investigated at the IGISOL facility. The studied nuclei, 81Y, 81Sr, 81mKr, 85Nb, 85Zr, 86Mo and 86Nb, were produced by a 32S beam from the Jyv?skyl? isochronous cyclotron on 54Fe and natNi targets. The internal conversion coefficient for a 190.5 keV isomeric transition in 81mKr has been measured and the internal transition rate has been determined. The internal transition rate has been used to estimate
a neutrino capture rate on 81Br, which yields a log ft of 5.13±0.09 for the reaction 81Br( ν, e
-)81mKr. A new isomer with a half-life of 3.3±0.9 s has been observed in 85Nb. The existence of an earlier reported isomer with a half-life of 56 s in 86Nb has not been confirmed. 相似文献
11.
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
12.
F. P. Heßberger S. Antalic B. Streicher S. Hofmann D. Ackermann B. Kindler I. Kojouharov P. Kuusiniemi M. Leino B. Lommel R. Mann K. Nishio S. Saro B. Sulignano 《The European Physical Journal A - Hadrons and Nuclei》2005,26(2):233-239
The decay of odd-mass mendelevium isotopes ( A = 247-255) has been studied by means of α-γ spectroscopy. Strong evidence for a small α branch in the decay of 253Md was found. γ lines in coincidence with α-decays of 247, 249, 251, 253Md have been observed for the first time. Levels in the einsteinium daughter nuclei were assigned on the basis of α-γ coincidence
measurements. An energy systematics of the 7/2-[514] Nilsson level could be established, showing a correlation with the deformation parameter β2 of the corresponding nuclei. The results are compared with theoretical predictions 相似文献
13.
U.C. Bergmann M.J.G. Borge J. Cederkäll C. Forssén E. Fumero H.O.U. Fynbo H. Gausemel H. Jeppesen B. Jonson K. Markenroth T. Nilsson G. Nyman K. Riisager H. Simon O. Tengblad L. Weissman F. Wenander K. Wilhelmsen Rolander 《The European Physical Journal A - Hadrons and Nuclei》2001,12(3):279-284
The β-decays of the neutron-rich nuclei 12Be and 29Ne have been studied. The statistical correlations between the almost identical half-lives of 12Be and its daughter 12B are analysed for a large sample of 12Be decay data. Stringent mutual bounds are obtained on the parameter set, leading to a precise determination of the 12Be half-life of 21.50±0.04 ms. From a simultaneous detection of β-particles and neutrons from the decay of 29Ne the neutron emission probability, Pn, is determined to 17±5%. No indication of two-neutron emission is seen from this nucleus. An upper limit of 2.2% (90% confidence
level) is established for P2n.
Received: 3 May 2001 / Accepted: 6 August 2001 相似文献
14.
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
15.
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
16.
A. Dzyuba V. Kleber M. Büscher V. P. Chernyshev S. Dymov P. Fedorets V. Grishina C. Hanhart M. Hartmann V. Hejny L. Kondratyuk V. Koptev P. Kulessa Y. Maeda T. Mersmann S. Mikirtychyants M. Nekipelov D. Prasuhn R. Schleichert A. Sibirtsev H. J. Stein H. Ströher I. Zychor 《The European Physical Journal A - Hadrons and Nuclei》2006,29(2):245-251
The reaction pp → dK
+ˉ has been investigated at excess energies Q = 47.4 and 104.7MeV above the K
+ˉ threshold at COSY Jülich. Coincident dK+ pairs were detected with the ANKE spectrometer, and subsequently ∼ 2000 events with a missing ˉ invariant mass were identified,
which fully populate the Dalitz plot. The joint analysis of invariant mass and angular distributions reveals s-wave dominance between the two kaons, in conjunction with a p-wave between the deuteron and the kaon pair, i.e.
Kˉ production via the a
0
+(980) channel. Integration of the differential distributions yields total cross-sections of σ(pp → dK
+ˉ) = (38±2stat±14syst)nb and (190±4stat±39syst)nb for the low and high Q value, respectively. 相似文献
17.
W. Ketter W. Heil G. Badurek M. Baron E. Jericha R. Loidl H. Rauch 《The European Physical Journal A - Hadrons and Nuclei》2006,27(2):243-256
Improved knowledge of the real part of the neutron scattering length of 3He is important for further development of nuclear few-body theory, as well as for a thorough understanding of neutron scattering
off quantum liquids. The real part of the bound incoherent neutron scattering length bi' has recently been measured directly with an experimental uncertainty of better than 1% by means of spin echo spectrometry.
The uncertainty of the more fundamental bound multiplet scattering lengths b±' is thus limited by today's 1.2% uncertainty of the spin-independent coherent part bc'. Employing the skew-symmetric perfect crystal Si-interferometer at the S18 experimental site at ILL, Grenoble, we have re-measured
the real part of the bound coherent neutron scattering length bc' of 3He. Our result bc' = 6.010(21)fm exhibits a significant deviation compared to the latest accepted value bc' = 5.74(7)fm (H. Kaiser, H. Rauch, G. Badurek, W. Bauspiess, U. Bonse, Z. Phys. A 291, 231 (1979)). Including the known value of the incoherent neutron scattering length, we obtain new values for the real parts
of the free singlet and triplet scattering lengths, a-' = 7.573(30)fm and a+' = 3.480(18)fm. Our result contravenes by more than 7 standard deviations the measurement of the same physical quantity that
has recently been performed by a group at NIST in a very similar experiment (P.R. Huffman, D.L. Jacobson, K. Schoen, M. Arif,
T.C. Black, W.M. Snow, S.A. Werner, Phys. Rev. C 70, 014004 (2004)) which yielded bc' = 5.853(7)fm. 相似文献
18.
F. Vanderbist P. Leleux C. Angulo E. Casarejos M. Couder M. Loiselet G. Ryckewaert P. Descouvemont M. Aliotta T. Davinson Z. Liu P. J. Woods 《The European Physical Journal A - Hadrons and Nuclei》2006,27(2):183-186
The 15O(α,α)15O elastic scattering is investigated using a 15O radioactive beam and a He gas cell limited by Mylar windows. The width of a 19Ne state at an excitation energy of 5.35MeV is measured as Γα = 3.2±1.6keV, in agreement with charge symmetry estimate. 相似文献
19.
R. Álvarez-Rodrıguez E. Garrido A. S. Jensen D. V. Fedorov H. O. U. Fynbo 《The European Physical Journal A - Hadrons and Nuclei》2007,31(3):303-317
The hyperspherical adiabatic expansion is combined with complex scaling and used to calculate low-lying nuclear resonances
of 12C in the 3α model. We use Ali-Bodmer potentials and compare results for other potentials α-α with similar 8Be properties. A three-body potential is used to adjust the 12C resonance positions to desired values extending the applicability of the method to many-body systems decaying into three
α-particles. For natural choices of three-body potentials we find 14 resonances below the proton separation threshold, i.e. two 0+, three 2+, two 4+, one of each of 1±, 2-, 3±, 4-, and 6+. The partial-wave decomposition of each resonance is calculated as a function of the hyperradius. Strong variation is found
from small to large distance. The connection to previous experimental and theoretical results is discussed and agreements
as well as disagreements are emphasized. 相似文献
20.
C. Wheldon Tz. Kokalova W. von Oertzen S. Thummerer H. G. Bohlen B. Gebauer A. Tumino T. N. Massey G. de Angelis M. Axiotis A. Gadea Th. Kröll N. Mărginean D. R. Napoli M. De Poli C. Ur D. Bazzacco S. M. Lenzi C. Rossi Alvarez S. Lunardi R. Menegazzo P. G. Bizzeti A. M. Bizzeti-Sona 《The European Physical Journal A - Hadrons and Nuclei》2005,26(3):321-326
Cluster states up to 12 MeV in the stable light nucleus 21Ne, based on the 16O + n + α molecular configurations, have been populated in the incomplete-fusion reaction 16 8O(73Li, np)2110Ne at 29.4 MeV. The observation of both intra- and inter-band transitions leads to a re-interpretation of some levels in the
Kπ =
- and Kπ =
- bands. The implications of this re-ordering on the octupole doublet bands are examined. The data allow a more accurate determination
of some previously uncertain level energies. The “missing” Iπ =
- level is also discussed. 相似文献