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1.
2.
A. V. Burenin 《Optics and Spectroscopy》2009,107(2):228-234
An algebraic model that describes the internal dynamics of the ionic complexes ArH3+ and ArD3+ in the ground electronic-vibrational state taking into account the torsional motion of the structure of identical hydrogen
nuclei is constructed by symmetry-group chain methods. It is important that the correctness of this model is only limited
by the correctness of the choice of geometric symmetry of the internal dynamics of the ionic complex. 相似文献
3.
A. P. Severyukhin N. N. Arsenyev N. Pietralla V. Werner 《Physics of Atomic Nuclei》2016,79(4):469-473
Starting fromthe Skyrme interaction f_ together with the volume pairing interaction, we study the g factors for the 21,2+ excitations of 132,134,136Te. The coupling between one- and two-phonon terms in the wave functions of excited states is taken into account within the finite-rank separable approximation. Using the same set of parameters we describe the available experimental data and give the prediction for 136Te, g(21+) = ?0.18 in comparison to +0.32 in the case of 132Te. 相似文献
4.
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
5.
H. Cherkani-Hassani D. S. Belic J. J. Jureta J. Lecointre P. Defrance 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2010,58(1):85-94
Absolute cross-sections for electron-impact dissociative ionization of C2
H2+ and C2 D2+ to CH+, C+, C2+ , H+, CH2+
and C2D+ fragments are determined for electron energies ranging
from the corresponding threshold to 2.5 keV. Results obtained in a crossed
beams experiment are analyzed to estimate the contribution of dissociative
ionization to each fragment formation. The dissociative ionization cross
sections are seen to decrease for more than an order of magnitude, from
CH+ (5.37±0.10) × 10-17 cm2 over C+ (4.19±
0.16) × 10-17 cm2, C2D+ (3.94±0.38) ×
10-17 cm2, C2+ (3.82±0.15) × 10-17 cm2
and H+ (3.37±0.21) × 10-17 cm2 to CH2+
(2.66±0.14) × 10-18 cm2. Kinetic energy release
distributions of fragment ions are also determined from the analysis of the
product velocity distribution. Cross section values, threshold energies and
kinetic energies are compared with the data available from the literature.
Conforming to the scheme used in the study of the dissociative excitation of
C2H2+
( C2 D2+ )\left( {\rm C}_2 {\rm D}_2^+ \right), the cross-sections are presented in
a format suitable for their implementation in plasma simulation codes. 相似文献
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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):438-440
Single-particle energies E nlj of neutron states in the 28 68 Ni40 nucleus are estimated on the basis of extrapolation of the experimental values of E nlj in the 58,60,62,64Ni isotopes. The data obtained are compared with the results of calculation within the dispersion optical model. 相似文献
8.
V. F. Elesin N. N. Degtyarenko N. V. Matveev A. I. Podlivaev L. A. Openov 《Journal of Experimental and Theoretical Physics》2005,101(1):44-55
The existence of a metastable cluster He 4 * with total spin S = 2 is predicted. The cluster consists of two covalently bound excited spin-polarized triplet He 2 * molecules and is rectangular in shape. The electron wavefunctions, the dependence of the energy He 4 * system on the distance between the He 2 * triplet molecules, the atomic spacing, the frequency spectrum of natural oscillations of the cluster, and other characteristics are calculated from first principles. It is shown that the metastable state is formed if one of the excited He 2 * molecules is in the 3Σ u + state, while the other is in the 3Πg state. The radiation lifetime τ of the metastable cluster He 4 * is calculated; it is found to range from 100 to 200 s, which is much longer than the lifetime τ ≈ 20 s of the triplet molecule He 2 * (3Σ u + ). The height U ≈ 0.5 eV of the potential barrier preventing the departure from the local energy minimum is determined. The energy Eacc ≈ 9 eV/atom accumulated in the He 4 * cluster is calculated; this energy considerably exceeds the energy of known chemical energy carriers. It is shown that the accumulated energy is released virtually completely during decomposition of the He 4 * cluster into individual helium atoms. This means that helium clusters are a promising material with a high accumulated energy density (HEDM). 相似文献
9.
D. Hennequin P. Verkerk 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2010,57(1):95-104
The dynamics of cold atoms in conservative optical lattices obviously depends on the geometry of the lattice. But very similar
lattices may lead to deeply different dynamics. In a 2D optical lattice with a square mesh, it is expected that the coupling
between the degrees of freedom leads to chaotic motions. However, in some conditions, chaos remains marginal. The aim of this
paper is to understand the dynamical mechanisms inhibiting the appearance of chaos in such a case. As the quantum dynamics
of a system is defined as a function of its classical dynamics – e.g. quantum chaos is defined as the quantum regime of a
system whose classical dynamics is chaotic – we focus here on the dynamical regimes of classical atoms inside a well. We show
that when chaos is inhibited, the motions in the two directions of space are frequency locked in most of the phase space,
for most of the parameters of the lattice and atoms. This synchronization, not as strict as that of a dissipative system,
is nevertheless a mechanism powerful enough to explain that chaos cannot appear in such conditions. 相似文献
10.
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
11.
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
12.
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
13.
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
14.
Careful review of all the evidence makes it clear that at least three states are important at 12.4-MeV excitation in 20Ne (four, if the broad (2+) at 12.5 MeV is included). The three states are 3 - , 0 + , and 1 + (0+). The latter, which is quite strong in 19F (3He, d) singles, is probably the state observed in coincidence with 6.13-MeV γ-rays in 19F(3He, dγ).
Received: 19 August 2002 / Accepted: 28 October 2002 / Published online: 17 January 2003
RID="a"
ID="a"e-mail: fortune@physics.upenn.edu
Communicated by D. Guerreau 相似文献
15.
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L. Batist M. Górska H. Grawe Z. Janas M. Kavatsyuk M. Karny R. Kirchner M. La Commara I. Mukha A. Plochocki E. Roeckl 《The European Physical Journal A - Hadrons and Nuclei》2010,43(1):45-53
Excited states of the 49107In nucleus were populated through the 78Se ( 32S , p2n) fusion-evaporation reaction at beam energy, E
lab = 125 MeV. The de-excitations were studied using in-beam g \gamma -ray spectroscopic techniques involving the Compton-suppressed clover detector array. The level scheme of 107In consisting of about seven bands is established up to spin ∼ 45/2ℏ with the addition of 25 new transitions. Spins and parities
of various levels have been assigned through the DCO and polarization measurements. The level structures observed in 107In have been interpreted in the framework of a microscopic theory based on the deformed Hartree-Fock (HF) and angular-momentum
projection techniques. Various bands are reproduced in band mixing calculations with the configurations involving high-W \Omega
p \pi
g
9/2 and n \nu
d
5/2 orbits, and low-W \Omega
p \pi
g
7/2 , n \nu
g
7/2 and n \nu
h
11/2 orbits. 相似文献
17.
H. Cherkani-Hassani S. Cherkani-Hassani D. S. Belic J. J. Jureta J. Lecointre P. Defrance 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2010,58(1):75-83
Absolute cross-sections for electron-impact ionization and dissociation of
C2H2+ and C2D2+ have been measured for electron energies
ranging from the corresponding thresholds up to 2.5 keV. The animated
crossed beams experiment has been used. Light as well as heavy fragment ions
that are produced from the ionization and the dissociation of the target
have been detected for the first time. The maximum of the cross-section for
single ionization is found to be (5.56 ± 0.03)× 10-17 cm2 around 140 eV. Cross-sections for dissociation of C2
H2+ (C2D2+) to ionic products are seen to decrease for two orders
of magnitude, from C2D+ (12.6 ± 0.3) × 10-17 cm2 over CH+(9.55 ± 0.06) × 10-17 cm2,
C+ (6.66 ± 0.05) × 10-17 cm2, C2+ (5.36 ± 0.27) × 10-17 cm2, H+ (4.73 ±
0.29) × 10-17 cm2 and CH2+ (4.56 ± 0.27) × 10-18 cm2 to H2+ (5.68 ± 0.49) ×
10-19 cm2. Absolute
cross-sections and threshold energies have been compared with the scarce
data available in the literature. 相似文献
18.
19.
The results of ab initio studies of the atomic and charge structure of small clusters and cluster ions formed by 13 and 19 argon atoms are reported. It was found that the icosahedral atomic structure is energetically the most favorable for such clusters. The calculations demonstrate that when a single electron is removed from a cluster, the excess positive charge is distributed primarily over the surface of the formed cluster ion. 相似文献
20.
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