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1.
O. V. Bespalova T. A. Ermakova E. A. Romanovskii T. I. Spasskaya A. A. Klimochkina 《Bulletin of the Russian Academy of Sciences: Physics》2009,73(6):816-819
Parameters of the neutron and proton dispersive optical potentials were determined by the earlier developed method for the
unstable double magic nuclei 2856Ni28 and 2878Ni50. They were used to calculate the neutron and proton single-particle energies of these nuclei near the Fermi energy. Good
agreement with the experimental data is obtained.
Original Russian Text ? O.V. Bespalova, T.A. Ermakova, E.A. Romanovskii, T.I. Spasskaya, A.A. Klimochkina, 2009, published
in Izvestiya Rossiiskoi Akademii Nauk. Seriya Fizicheskaya, 2009, Vol. 73, No. 6, pp. 863–866. 相似文献
2.
V. L. Litnevsky G. I. Kosenko F. A. Ivanyuk V. V. Pashkevich 《Physics of Atomic Nuclei》2012,75(1):37-44
The effect of the shell structure of colliding nuclei in calculating the entrance channel on the ensuing evolution of the
product system is investigated. The entrance channel is calculated under the assumption of the nose-to-nose orientation of
colliding nuclei. The following three reactions involving nuclei that are deformed in the ground state are considered: 42100Mo + 42100Mo → 84100Po, 42100Mo + 46100Pd → 88210Ra, and 46110Pd + 46110Pd → 92220U. The state of the system at the point of touching is determined by the results obtained by calculating the entrance reaction
channel. The shape of the system is specified by three collective coordinates (deformation parameters). The evolution of collective
coordinates of the system is described in terms of Langevin equations. The potential energy of the system of colliding nuclei
is calculated with allowance for their shell structure. It is shown that allowance for individual features of interacting
nuclei in the entrance channel of the fusion-fission reactions makes it possible to obtain, for the reactions being considered,
cross sections for evaporation-residue formation that are closer to available experimental data than their liquid-drop counterparts. 相似文献
3.
S. A. Astashkevich B. P. Lavrov A. V. Modin I. S. Umrikhin 《Russian Journal of Physical Chemistry B, Focus on Physics》2008,2(1):16-31
A statistical analysis of the available literature data and data obtained in this work on the wave numbers of the lines that
appear in triplet-triplet rovibronic transitions of the H2 molecule was performed. This allowed us to verify and refine the controversial identification of spectral lines and find
the optimum rovibronic level energy values for the c
3Π
u
±, r
3Π
g
−, and s
3Δ
g
− states. The ratios between the line strengths of the P, Q, and R branches of the (4dπ)r
3Π
g
−, (4dδ)s
3Δ
g
− → (2pπ)c
3Π
u
± band systems of the H2 molecule were measured systematically. The calculation results obtained in the Frank-Condon approximation differed substantially
(by up to two orders of magnitude) from the experimental data. The dependences of the ratios between rovibronic line strengths
of the r
3Π
g
− → c
3Π
u
± and s
3Δ
g
− → c
3Π
u
± transitions on the rotational quantum number N′ of the upper level were found to correlate with each other. The deviations of adiabatic theory increase as N′ grows, which is evidence of an important role played by electronic-rotational interactions in the perturbation of transition
probabilities. The experimental ratios between the probabilities of rovibronic transitions satisfactorily agree with the results
of calculations within the framework of the simple nonadiabatic model taking into account electronic-rotational interaction
of radiating adiabatic states in the approximation of pure precession. The dependences of transition probabilities on N′ were obtained for the first time for the first four diagonal bands of the r
3Π
g
−, s
3Δ
g
− → c
3Π
u
± transitions.
Original Russian Text ? S.A. Astashkevich, B.P. Lavrov, A.V. Modin, I.S. Umrikhin, 2008, published in Khimicheskaya Fizika,
2008, Vol. 27, No. 2, pp. 22–38. 相似文献
4.
V. I. Isakov 《Physics of Atomic Nuclei》2008,71(4):713-723
Binding and one-nucleon separation energies are calculated for nuclei with 20 ≤ Z, N ≤ 28, where both protons and neutrons occupy the 1f
7/2 valence subshells. To this aim, two different methods are applied. The first method employs the self-consistent approach
with the effective Skyrme forces and pairing interaction, while the second one makes use of the semiempicial multiparticle
shell model with the effective two-body matrix elements of the interaction defined from the empirical data. The intercomparison
between the two methods is carried out.
The text was submitted by the authors in English. 相似文献
5.
The optimized configurations, electronic structures, charge transfers, band gaps, total energies, cohesive energies, electron
density maps, infrared absorption spectra, Raman spectra, and relevant modes of natural acoustic vibrations for the semiconductor
clusters C24, B12N12, Si12C12, Zn12O12, and Ga12N12 are calculated using the ab initio Hartree-Fock method in the 6–31G basis set.
Original Russian Text ? V.V. Pokropivny, L.I. Ovsyannikova, 2007, published in Fizika Tverdogo Tela, 2007, Vol. 49, No. 3,
pp. 535–542. 相似文献
6.
ZEUS Collaboration M. Derrick D. Krakauer S. Magill D. Mikunas B. Musgrave J. Repond R. Stanek R. L. Talaga H. Zhang et al. 《Zeitschrift fur Physik C Particles and Fields》1995,69(1):607-620
We report on a measurement of the proton structure functionF
2 in the range 3.5×10−5≤x≤4×10−3 and 1.5 GeV2≤Q
2≤15GeV2 at theep collider HERA operating at a centre-of-mass energy of √s=300GeV. The rise ofF
2 with decreasingx observed in the previous HERA measurements persists in this lowerx andQ
2 range. TheQ
2 evolution ofF
2, even at the lowestQ
2 andx measured, is consistent with perturbative QCD.
supported by EU HCM contract ERB-CHRX-CT93-0376 相似文献
7.
T. Ishii S. Shigematsu H. Makii M. Asai K. Tsukada A. Toyoshima M. Matsuda A. Makishima T. Shizuma J. Kaneko I. Hossain H. Toume M. Ohara S. Ichikawa T. Kohno M. Ogawa 《Physics of Atomic Nuclei》2007,70(8):1457-1461
We have measured deexcitation γ rays in the neutron-rich nuclei of 240U, 246Pu, and 250Cm produced by the (18O, 16O) two-neutron transfer reactions, in coincidence with the 16O particles using Si ΔE−E detectors. The γ rays in these nuclei were identified by selecting the kinetic energies of 16O particles, which correspond to the excitation energies in the residual nuclei below the neutron separation energies. The
ground-state bands of 240U, 246Pu, and 250Cm were established up to 12+ states and the K
π = 0− octupole band of 240U was established up to 9− states. The systematics of the moments of inertia of the ground-state bands for actinide nuclei shows that the deformed subshell
closure at N = 152 is sustained for 96Cm isotopes and that it disappears for 94Pu isotopes.
The text was submitted by the authors in English. 相似文献
8.
Absolute cross sections σ−(E, N) of electron attachment to clusters (H2O)
N
, (N2O)
N
, and (N2)
N
for varying electron energy E and cluster size N are measured by using crossed electron and cluster beams in a vacuum. Continua of σ−(E) are found that correlate well with the functions of electron impact excitation of molecules’ internal degrees of freedom.
The electron is attached through its solvation in a cluster. In the formation of (H2O)
N
−
, (N2O)
N
−
, and (N2)
N
−
, the curves σ−(N) have a well-defined threshold because of a rise in the electron thermalization and solvation probability with N. For (H2O)900, (N2O)350, and (N2)260 clusters at E = 0.2 eV, the energy losses by the slow electron in the cluster are estimated as 3.0 × 107, 2.7 × 107, and 6.0 × 105 eV/m, respectively. It is found that the growth of σ− with N is the fastest for (H2O)
N
and (N2)
N
clusters at E → 0 as a result of polarization capture of the s-electron. Specifically, at E = 0.1 eV and N = 260, σ− = 3.0 × 10−13 cm2 for H2O clusters, 8.0 × 10−14 cm2 for N2O clusters, and 1.4 × 10−15 cm2 for N2 clusters; at E = 11 eV, σ− = 9.0 × 10−16 cm2 for (H2O)200 clusters, 2.4 × 10−14 cm2 for (N2O)350 clusters, and 5.0 × 10−17 cm2 for (N2)260 clusters; finally, at E = 30 eV, σ− = 3.6 × 10−17 cm2 for (N2O)10 clusters and 3.0 × 10−17 cm2 for (N2)125 clusters.
Original Russian Text ? A.A. Vostrikov, D.Yu. Dubov, 2006, published in Zhurnal Tekhnicheskoĭ Fiziki, 2006, Vol. 76, No. 12,
pp. 1–15. 相似文献
9.
The known and new heterogeneous spectral data on the triplet states a
3Σ
u
+
, 23Πg, 23Σ
g
+
, 33Πg, and 43Σ
g
+
of the K2 dimer are simultaneously fitted. The data published in J. Mol. Spectrosc. 234, 41 (2005) are refined. The new information used in the analysis contains the data on the 23Σ
g
+
state, which have not been considered previously. The range of internuclear distances where the potential function of the
lowest triplet state a
3Σ
u
+
is defined is extended.
Original Russian Text ? V.B. Sovkov, V.S. Ivanov, D. Li, F. Xie, Li Li, 2007, published in Optika i Spektroskopiya, 2007,
Vol. 103, No. 5, pp. 747–751. 相似文献
10.
O. V. Bespalova I. N. Boboshin V. V. Varlamov T. A. Ermakova B. S. Ishkhanov S. Yu. Komarov H. Koura E. A. Romanovskii T. I. Spasskaya 《Bulletin of the Russian Academy of Sciences: Physics》2009,73(6):820-823
Single-particle energies corresponding to the maximum value of the spectroscopic factor were obtained for the proton states
near the Fermi energy in the 58,60,62,64Ni nuclei by the joint evaluation of the data on the stripping and pickup reactions on the same nucleus. These results are
compared with the center-of-gravity energies of the single-particle state fragment distributions obtained by the same method
and with the single-particle energies calculated with the potential of X. Koura and M. Yamada and with the dispersive optical
model potential. The single-particle state fragmentation effect is discussed.
Original Russian Text ? O.V. Bespalova, I.N. Boboshin, V.V. Varlamov, T.A. Ermakova, B.S. Ishkhanov, S.Yu. Komarov, H. Koura,
E.A. Romanovskii, T.I. Spasskaya, 2009, published in Izvestiya Rossiiskoi Akademii Nauk. Seriya Fizicheskaya, 2009, Vol. 73,
No. 6, pp. 867–870. 相似文献
11.
F. E. H. van Eijkern G. A. Timmer F. Meurders P. W. M. Glaudemans 《Zeitschrift für Physik A Hadrons and Nuclei》1976,278(4):337-345
Shell-model calculations for positive-parity levels of A=28–32 nuclei have been performed in a 1d5/2 2s1/2 1d3/2 configuration space. Configuration mixing of at most 250 lowest-lying pure configurations for each (A, J, T) set was taken into account. By a variation of the four effective interaction (MSDI) parameters and three single-particle energies a search was made for the best fit of the calculated energies to the experimental values. The average deviation between theory and experiment for the energies of the 110 fitted levels is 0.44 MeV. By adjusting all the 63 two-body matrix elements (ASDI) and the three single-particle energies, the average deviation of the binding energies was reduced to 0.16 MeV. For the lowest 10–15 levels in all A=28–32 nuclei a one to one correspondence exists between theory and experiment. Electromagnetic transition strengths were calculated both with MSDI and with ASDI wave functions. The ASDI wave functions reproduce the experimental E2 data much better than the MSDI wave functions. For the M1 transition strengths only a minor improvement has been achieved. 相似文献
12.
The influence of the replacement of Mn ions in the La0.7Ca0.3Mn1 − y
Fe
y
O3 compounds (0 ≤ y ≤ 0.09) by another transitional metal, Fe, was studied. The radii of both ions are almost identical, which makes the effect
of the transitional metal on the physical properties of manganites more transparent. The crystal structure of three samples
(with y = 0, 0.03, 0.09) is studied in the temperature range T = 1.5–300 K by neutron powder diffraction. All investigated samples belong to the orthorhombic space group Pnma (62). It is confirmed that Fe ions occupy the Mn positions in the unit cell. As the Fe concentration increases, the saturation
value of the spontaneous magnetic moment and the Curie temperature decrease, but the ground state remains ferromagnetic for
0 ≤ y ≤ 0.1. The saturation values of the magnetic moments at T = 1.5 K are m
FM = 3.72(3), 3.40(3), and 3.27(3) μ
B
/Mn for the samples with an Fe concentration y = 0, 0.03, and 0.09, respectively.
Original Russian Text ? A.I. Kurbakov, V.S. Zakhvalinskii, R. Laiho, 2007, published in Fizika Tverdogo Tela, 2007, Vol. 49,
No. 4, pp. 691–695. 相似文献
13.
O. V. Bespalova T. A. Ermakova A. A. Klimochkina E. A. Romanovsky T. I. Spasskaya 《Physics of Atomic Nuclei》2013,76(12):1482-1489
Experimental single-particle proton energies in spherical and nearly spherical 20 ? Z ? 28 medium-mass nuclei and their counterparts evaluated with the aid of data formirror nuclei were analyzed on the basis of the dispersive optical model. The parameters of the dispersive optical potential were extrapolated to the region of unstable nuclei, and the values obtained in this way were then used to predict the single-particle proton energies in the 20 ? N ? 50 nuclei under study. The evolution of the particle-hole energy gap was traced, and features peculiar to single-particle spectra of magic and nonmagic nuclei were revealed by comparing single-particle energies with proton-separation energies. 相似文献
14.
Victoria E. Buravtsova Vladimir S. Guschin Yuri E. Kalinin Sergey A. Kirov Eugenia V. Lebedeva Songsak Phonghirun Alexander V. Sitnikov Nikolay E. Syrev Igor T. Trofimenko 《Central European Journal of Physics》2004,2(4):566-578
For nanodimensional magnetically inhomogeneous amorphous granular films of the system (Co84Nb14Ta2)
x
(SiO2)100−x
, 30≤x≤60 at.% the concentration dependences of the magnetooptical Kerr effect (MOKE) spectra and FMR have been investigated. The
observed changes in the MOKE and FMR spectra are associated with transformations of microstructure and topology of the nanocomposites.
For the compositions within the percolation region the transversal Kerr effect increases by an order of magnitude. 相似文献
15.
I.P. Johnstone L.D. Skouras 《The European Physical Journal A - Hadrons and Nuclei》2001,11(2):125-136
The matrix elements of the effective Hamiltonian in the 0g
9/2-1p
1/2 space are determined by a least-square fit to the energies of 477 levels of nuclei with 38≤Z≤50 and 47≤N≤50. The results of the calculation are found to be in better agreement with experiment than those obtained with previously
determined interactions.
Received: 31 May 2001 / Accepted: 14 June 2001 相似文献
16.
R. B. Morgunov E. V. Kurganova T. G. Prokhorova é. B. Yagubski S. V. Simonov R. P. Shibaeva 《Physics of the Solid State》2008,50(4):684-690
Layered single crystals of the (BEDO-TTF)6[M(CN)6](H3O,CH3CN)2 (M = Fe, Cr) compounds with alternating conducting layers of BEDO-TTF and [M(CN)6](H3O,CH3CN)2 are studied. The contributions to the magnetic susceptibility from charge carriers in BEDO-TTF layers and from the subsystem of localized magnetic moments of iron (or chromium) transition metal complexes are separated
for both compounds under investigation. It is revealed that the crystals with [Fe(CN))6]3− anions at a temperature of ∼80 K and the crystals with [Cr(CN))6]3− anions at ∼30 K undergo magnetic transitions which are accompanied by drastic changes in the parameters of the EPR lines
associated with the BEDO-TTF layers and the subsystem of localized spins of transition metal complexes. It is established that the presence of the BEDO-TTF layers in the structure affects the magnetic properties of iron and chromium hexacyanide complexes.
Original Russian Text ? R.B. Morgunov, E.V. Kurganova, T.G. Prokhorova, E.B. Yagubskiĭ, S.V. Simonov, R.P. Shibaeva, 2008,
published in Fizika Tverdogo Tela, 2008, Vol. 50, No. 4, pp. 657–663. 相似文献
17.
I. N. Boboshin V. V. Varlamov B. S. Ishkhanov E. A. Romanovsky 《Physics of Atomic Nuclei》2007,70(8):1363-1368
New information about energies and occupation probabilities of neutron and proton single-particle (hole) subshells in even—even
nuclei was obtained in previous studies applying the method of putting into correspondence all available data on one-nucleon
pickup and stripping reactions. The most important and interesting resultwas identification of several nuclei as new magic
ones. Namely, itwas found that a filling of the neutron 2d
5/2 subshell in 96Zr makes this nuclide a magic one. Moreover, changes in proton subshell energies with increasing neutron number N are accompanied by an increasing energy gap between closed 2p
1/2 and empty 1g
9/2 subshells. Thus, the neutron number N = 56 appears to be a magic one if the proton number Z is equal to 40. The proton number Z = 40 manifests properties of the magic number in 96Zr. Therefore, 96Zr was identified as a new double-magic nucleus. Further investigations revealed that the energy of the first 2+ state E(2
1
+
) in 96Zr is much higher than that in the neighboring isotopes and isotones, whereas the ratio E(4
1
+
)/E(2
1
+
) and the quadrupole deformation parameter β2 are, vice versa, clearly lower. Moreover, the A dependence of the neutron separation energy B(n) in Zr isotopes has an irregularity at N = 56 which is typical of magic nuclei. As a result of these investigations, it was found that, near the Fermi energy, there
are two closed subshells with the same (and large) angular momentum j = 5/2 (viz. π1f
5/2 and ν2d
5/2). We call this situation the jj connection. The magic numbers under discussion (Z = 40 and N = 56) are achieved at the points where both subshells are closed, and in addition, the closed subshell with j = 1/2, π2p
1/2, occurs above the proton π1f
5/2 subshell. This looks like a result of some additional attractive proton-neutron interaction. It was found that application
of this scheme (jj connection) to other subshells reveals several other new magic nuclei: 54Ca (closed π1d
3/2 and ν2p
3/2 together with closed ν2p
1/2), 30S and 30Si (closed π1d
5/2 and ν1d
5/2 together with closed (π/ν)2s
1/2), and 14O and 14C (closed π1p
3/2 and ν1p
3/2 together with closed ν2p
1/2).
The text was submitted by the authors in English. 相似文献
18.
H.F. Lü J. Meng S.Q. Zhang S.-G. Zhou 《The European Physical Journal A - Hadrons and Nuclei》2003,17(1):19-24
Properties of single- Λ and double- Λ hypernuclei for even-N Ca isotopes ranging from the proton dripline to the neutron dripline are studied using the relativistic continuum Hartree-Bogoliubov
theory with a zero-range pairing interaction. Compared with ordinary nuclei, the addition of one or two Λ-hyperons lowers
the Fermi level. The predicted neutron dripline nuclei are, respectively, 75
ΛCa and 76
2ΛCa, as the additional attractive force provided by the Λ-N interaction shifts nuclei from outside to inside the dripline.
Therefore, the last bound hypernuclei have two more neutrons than the corresponding ordinary nuclei. Based on the analysis
of two-neutron separation energies, neutron single-particle energy levels, the contribution of continuum and nucleon density
distribution, giant halo phenomena due to the pairing correlation, and the contribution from the continuum are suggested to
exist in Ca hypernuclei similar to those that appear in ordinary Ca isotopes.
Received: 21 October 2002 / Accepted: 11 January 2003 / Published online: 8 April 2003 相似文献
19.
A. I. Reznikov S. Ya. Umanskii Yu. F. Chaikina 《Russian Journal of Physical Chemistry B, Focus on Physics》2010,4(2):203-209
Rate constants for electron-vibrational energy exchange Ar(3
P
2) + N2(X
1Σ
g
+, ν = 0) → Ar(1
S
0) + N2(C
3Π
u
, ν′), where ν′ = 0, 1, 2, were calculated. Calculations were performed taking into account the presence of a resonance in electron scattering
by N2(X
1Σ
g
+). As a result, the interaction of Ar(3
P
2) with N2(X
1Σ
g
+, ν = 0) was characterized by attraction and, in the end, intersection of electron-vibrational potential surfaces correlating
with Ar(3
P
2) + N2(X
1Σ
g
+, ν = 0) and Ar(1
S
0) + N2(C
3Π
u
, ν′) at interparticle distances of 2.5–3.5 ?. Exchange interaction at which electron-vibrational transitions in the region of
intersection of electron-vibrational transitions in the region of intersection of electron-vibrational potential surfaces
accompanied by spin exchange were induced was calculated by the asymptotic method. The rate constants determined at 300–600
K were on the order of 10−11−10−12 cm3/s and weakly increased as the temperature grew. Mainly the C
3Π
u
, ν′ = 0 state of the N2 molecule was populated. The calculation results were in satisfactory agreement with the experimental data obtained at 300
K. 相似文献
20.
Recently [see V.V. Anisovich et al., Yad. Fiz. 63, 1489 (2000)], the K-matrix solutions for the wave IJ
PC=00++ were obtained in the mass region 450–1900 MeV, where four resonances f
0(980), f
0(1300), f
0(1500), f
0(1750) and the broad state f
0(1530
−250
+90
) are located. Based on these solutions, partial widths are determined for scalar-isoscalar states decaying into the channels
ππ, KK
ηη, ηη′, ππππ and corresponding decay couplings.
From Yadernaya Fizika, Vol. 65, No. 8, 2002, pp. 1583–1590.
Original English Text Copyright ? 2002 by Anisovich, Nikonov, Sarantsev.
This article was submitted by the authors in English. 相似文献