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V. V. Varlamov A. I. Davydov V. N. Orlin N. N. Peskov 《Bulletin of the Russian Academy of Sciences: Physics》2017,81(6):664-669
Experimental photonuclear reaction cross sections obtained in experiments using quasimonoenergetic annihilation, monoenergetic tagged photons, and bremsstrahlung γ-radiation are analyzed using physical criteria for the reliability of data on the 89Y nucleus. It is found that the reliability of data on the cross sections of partial reactions (γ, 1n) and (γ, 2n), obtained by means of photoneutron multiplicity sorting, is highly doubtful. Reliable cross sections of reactions (γ, 1n) and (γ, 2n) are obtained using the experimental–theoretical method (ETM) for evaluating using both experimental cross sections of neutron yield reaction σexp(γ, xn) that are free of neutron multiplicity problems, and theoretically calculated F i theor ratios of the cross sections of definite (i) partial reactions to cross section σtheor(γ, xn). It is shown that the evaluated cross sections differ noticeably from the experimental data. 相似文献
3.
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
4.
The low-lying levels in 127La have been studied through the -decay of 127Ce ( T1/2 = 29s) produced by bombarding a natMo target with a 185-MeV 35Cl beam. Reaction products were on-line mass-separated, and -ray singles and - coincidence measurements were performed. Conversion electrons were also measured and multipolarities of transitions have been derived. The half-life of the 210.9-keV level was determined to be (1.9±0.3)ns by the - delayed coincidence technique. The level scheme obtained has been compared with calculations based on the Nilsson model. 相似文献
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Vinod Kumar Pragya Das R.P. Singh S. Muralithar R.K. Bhowmik 《The European Physical Journal A - Hadrons and Nuclei》2003,17(2):153-157
The fusion evaporation reaction 122Sn(14N, 4n)132La was used to populate the high-spin states of 132La at the beam energy of 60 MeV. A new band consisting of mostly E2 transitions has been discovered. This band has the interesting links to the ground state 2- and the isomeric state 6-. A new transition of energy 351 keV connecting the low-spin states of the positive-parity band based on the πh
11/2 ⊗ νh
11/2 particle configuration, has been found. This has played a very important role in resolving the existing ambiguities and inconsistencies
in the spin assignment of the band head.
Received: 12 August 2002 / Accepted: 18 March 2003 / Published online: 7 May 2003 相似文献
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A. Merli F. Sauer L. Wöste A. Lindinger 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,42(2):217-220
We report on isotope selective three-photon ionization of
two isotopomers of KRb by applying evolution strategies. The
particularity of this experiment is based on the high resolution
phase and amplitude modulation of the fs-laser pulses provided by a
2 × 640 pixel pulse shaper. The optimization in a closed feedback
loop performed with spectrally broad pulses centered at 840 nm shows
high enhancements of one isotopomer at the expense of the other
isotopomer and vice versa. From the optimal laser field we aim to
gain details about the selective ionization sequence and the
wavepacket evolution on the involved vibrational states. 相似文献
9.
Within the framework of the single-channel approximation, an {αtd} model of the 9
Be nucleus is presented. A comparative analysis of the t 6
Li wave functions describing relative motion of bound states constructed in {ααn} and {αtd} cluster representations is carried out on the example of calculations of the 9
Be(γ,t0)6
Li process characteristics.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 85–89, January, 2008. 相似文献
10.
Aparajita Dey S. Bhattacharya C. Bhattacharya K. Banerjee T. K. Rana S. Kundu S. R. Banerjee S. Mukhopadhyay D. Gupta R. Saha 《The European Physical Journal A - Hadrons and Nuclei》2009,41(1):39-51
Inclusive energy distributions for light charged particles (p , d , t and have been measured in the 20Ne (158, 170, 180, 200 MeV) + 12C
reactionsintheangularrange$10°$ - - $50°$.Exclusivelight-charged-particleenergydistributionmeasurementswerealsodoneforthesamesystemat158 MeVbombardingenergybyin - planelightchargedparticle - - fragmentcoincidence.Pre - equilibriumcomponentshavebeenseparatedoutfromprotonenergyspectrausingthemovingsourcemodelconsideringtwosources.ThedatahavebeencomparedwiththepredictionsofthestatisticalmodelcodeCASCADE.Ithasbeenobservedthatsignificantdeformationeffectswereneededtobeintroducedinthecompoundnucleusinordertoexplaintheshapeoftheevaporated$d$,$t$energyspectra.Forprotons, evaporatedenergyspectrawereratherinsensitivetonucleardeformation, thoughangulardistributionscouldnotbeexplainedwithoutdeformation.Thedecaysequenceofthehot$32S$nucleushasbeeninvestigatedthroughexclusivelight - - charged - particlemeasurementsusingthe$20Ne$$(158 MeV) + $12C
reaction. Information on the sequential decay chain has been extracted through a comparison of the experimental data with
the predictions of the statistical model. It is observed from the present analysis that exclusive light-charged-particle data
may be used as a powerful tool to probe the decay sequence of hot light compound systems. 相似文献
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B. V. Zhuravlev A. A. Lychagin N. N. Titarenko V. G. Demenkov V. I. Trykova 《Physics of Atomic Nuclei》2011,74(3):335-340
The spectra of neutrons from the (p, n) reactions on 47Ti, 48Ti, 49Ti, 53Cr, and 54Cr nuclei were measured in the proton-energy range 7–11 MeV. The measurements were performed with the aid of a fast-neutron
spectrometer by the time-of-flight method over the base of the EGP-15 tandem accelerator of the Institute for Physics and
Power Engineering (IPPE, Obninsk). Owing to a high resolution and a high stability of the time-of-flight spectrometer used,
low-lying discrete levels could be identified reliably along with a continuum section of neutron spectra. An analysis of measured
data was performed within the statistical equilibrium and preequilibrium models of nuclear reactions. The relevant calculations
were performed by using the exact formalism of Hauser-Feshbach statistical theory supplemented with the generalized model
of a superfluid nucleus, the back-shifted Fermi gas model, and the Gilbert-Cameron composite formula for the nuclear level
density. The nuclear level densities for 47V, 48V, 49V, 53Mn, and 54Mn were determined along with their energy dependences and model parameters. The results are discussed together with available
experimental data and recommendations of model systematics. 相似文献
13.
O. V. Bespalova I. N. Boboshin V. V. Varlamov T. A. Ermakova B. S. Ishkhanov E. A. Romanovskii T. I. Spasskaya T. P. Timokhina 《Bulletin of the Russian Academy of Sciences: Physics》2007,71(3):428-433
The change in the neutron single-particle structure of (1f?2p)-shell magic nuclei near the Fermi energy with an increase in the number of protons in the 1f 7/2 subshell from 0 for 48Ca to 8 for 56Ni has been investigated. Good agreement of the experimental and estimated values of the single-particle energies E nlj of the bound states of neutrons in these nuclei with the results of calculations within the dispersive optical model is obtained. 相似文献
14.
M. A. Cardona B. Roussière J. Libert J. Genevey J. Sauvage the ISOCELE ISOLDE Collaborations 《The European Physical Journal A - Hadrons and Nuclei》2007,31(2):141-154
Excited states in 182Os were populated by the β+/EC decay of 182Ir following mass separation. Gamma-ray and conversion electron spectroscopy techniques were employed. Monopole (E0) contributions were determined in transitions populating the ground-state band. A systematic study of the low-spin structures
in the Os isotopes is presented and a detailed analysis in the framework of a microscopic configuration mixing approach is
performed. 相似文献
15.
T. Grahn J. Pakarinen L. Jokiniemi M. Albers K. Auranen C. Bauer C. Bernards A. Blazhev P. A. Butler S. Bönig A. Damyanova T. De Coster H. De Witte J. Elseviers L. P. Gaffney M. Huyse A. Herzáň U. Jakobsson R. Julin N. Kesteloot J. Konki Th. Kröll L. Lewandowski K. Moschner P. Peura M. Pfeiffer D. Radeck P. Rahkila E. Rapisarda P. Reiter K. Reynders M. Rudiger M. -D. Salsac S. Sambi M. Scheck M. Seidlitz B. Siebeck T. Steinbach S. Stolze J. Suhonen P. Thoele M. Thürauf N. Warr P. Van Duppen M. Venhart M. J. Vermeulen V. Werner M. Veselsky A. Vogt K. Wrzosek-Lipska M. Zielińska 《The European Physical Journal A - Hadrons and Nuclei》2016,52(11):340
16.
Wei Jiang YanLin Ye ZhiHuan Li ChengJian Lin QiTe Li YuCheng Ge JianLing Lou DongXing Jiang Jing Li ZhengYang Tian Jun Feng Biao Yang ZaiHong Yang Jie Chen HongLiang Zang Qiang Liu PengJie Li ZhiQiang Chen Yun Zhang Yang Liu XiaoHui Sun Jing Ma HuiMing Jia XinXing Xu Lei Yang NanRu Ma LiJie Sun 《中国科学:物理学 力学 天文学(英文版)》2017,60(6):062011
A transfer-reaction experiment of 9Be(9Be, 10Be)8Be was performed at a beam energy of 45 MeV. Excited states in 10Be up to 18.80 MeV are produced using missing mass and invariant mass methods. Most of the observed high-lying resonant states, reconstructed from the α + 6He and t + 7Li decay channels, agree with the previously reported results. In addition, two new resonances at 15.6 and 18.8 MeV are identified from the present measurement. The 18.55 MeV state is found to decay into both the t + 7Lig.s. and t + 7Li* (0.478 MeV) channels, with a relative branching ratio of 0.93 ± 0.33. Further theoretical investigations are encouraged to interpret this new information on cluster structure in neutron-rich light nuclei. 相似文献
17.
U. S. Udayachandran Thampy Ch. Rama Krishna Ch. Venkata Reddy B. Babu Y. P. Reddy P. S. Rao R. V. S. S. N. Ravikumar 《Applied magnetic resonance》2011,41(1):69-78
Cu2+-doped ZnO nanopowders, synthesized at room temperature by mild and simple solution method, are characterized by powder X-ray
diffraction (XRD), scanning electron microscopy (SEM), optical, electron paramagnetic resonance (EPR) and Fourier-transform
infrared (FT-IR) techniques. From XRD and SEM, the crystal structure is identified as hexagonal, and the average crystallite
size is around 53 nm. Lattice cell parameters are evaluated. The optical and EPR spectral investigations suggest that the
Cu2+ ion enters the host lattice in two tetragonally distorted octahedral sites. Crystal field, tetragonal field, spin Hamiltonian
and bonding parameters are estimated. 相似文献
18.
M. A. Naumenko V. V. Samarin Yu. E. Penionzhkevich N. K. Skobelev 《Bulletin of the Russian Academy of Sciences: Physics》2017,81(6):710-716
Experimental cross sections of formation of isotopes 46Sc (in reaction 6He + 45Sc), 196,198Au (in reaction 6He + 197Au), and 65Zn (in reaction 6He + 64Zn) are analyzed. The time-dependent Schrödinger equation for the outer neutrons of 6He and 197Au nuclei is solved numerically to calculate the probability of neutron transfer and transfer cross sections. In reaction 6He + 197Au, the contribution of fusion and subsequent evaporation to experimental data can be neglected, while the corresponding contributions to reactions 6He + 45Sc and 6He + 64Zn are considerable. Fusion–evaporation is taken into account using the computational code of the NRV knowledge base. The results of calculations are in satisfactory agreement with the experimental data. 相似文献
19.
A. V. Eliseev I. N. Meshkov V. A. Mikhailov A. O. Sidorin 《Physics of Particles and Nuclei Letters》2010,7(7):473-477
The main objective of the NICA project developed at the Joint Institute for Nuclear Research (JINR) is to conduct experimental
studies with colliding heavy ion beams in an energy range of 1–4.5 GeV/nucleonucleon with luminosity on the level of 1 × 1027 cm−2 s−1. In this paper the operation regime of the collider injection chain providing the bunch with experimentally desirable parameters
at the output of the Nuclotron is considered for gold ions as an example. 相似文献
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Zh. I. Adymov N. Burtebayev S. B. Sakuta 《Bulletin of the Russian Academy of Sciences: Physics》2011,75(7):914-916
Doppler shift attenuation was used to measure the lifetimes of 48Ti, 52Cr and 80Se nuclei excited states populated in the (n, n′γ) reaction using the neutron beam of the Republic of Kazakhstan’s WWR-K research
reactor. The measured data are in good agreement with the latest literature data. 相似文献