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1.
I. T. Obukhovsky 《Zeitschrift für Physik A Hadrons and Nuclei》1982,308(3):253-266
The spectrum and eigenfunctions of deuteronlike states in the quark bag for the configurationsS 6 andS 4 P 2 have been studied. The complete tables of the fractional parentage coefficients (f.p.c.) for these configurations in thej-j andL-S coupling schemes are presented. The universal method of calculation of the f.p.c. which is based on the complementarity of the unitary and permutation group, is considered. The method enable one to calculate the Clebsh-Gordon coefficients and the invariant symbols of the noted groups. It is shown that the lowest energy state of the configurationS 1 2/4 P 3 2/2 resembles the partial wave3 D 1 and can, therefore, be coupled to it in a deuteron. On the contrary, the lowest states in the configurationsS 1 2/6 andS 1 2/4 P 1 2/2 resemble the3 S 1-wave. 相似文献
2.
V. I. Kukulin I. T. Obukhovsky V. N. Pomerantsev P. Grabmayr A. Faessler 《Physics of Atomic Nuclei》2007,70(2):215-230
A new model for short-range isoscalar current in the deuteron and NN system is developed and tested on a variety of isoscalar magnetic observables such as the deuteron magnetic moment, magnetic
form factor, and the circular polarization of photons at
radiative capture at thermal neutron energies. The model for electromagnetic two-nucleon current proposed in the paper is
based on generation of an intermediate dibaryon in the short-range NN interaction. This intermediate dibaryon, in turn, is treated within the new model for intermediate and short-range NN interaction recently proposed by the present authors. The transition current model developed here satisfies the current conservation
relation by the construction. Our calculations have demonstrated that the new current model, using only one parameter (with
a clear physical meaning), is able to describe, in very good agreement with the experimental data, three basic deuteron observables
of magnetic type, viz., the magnetic moment, the photon circular polarization in the
process, and the structure function B(Q
2) up to Q
2 ≃ 60 fm−2.
The text was submitted by the authors in English. 相似文献
3.
Juliana S Luz Celso RR Ramos Márcia CT Santos Patricia P Coltri Fernando L Palhano Debora Foguel Nilson IT Zanchin Carla C Oliveira 《BMC biochemistry》2010,11(1):22
Background
The archaeal exosome is formed by a hexameric RNase PH ring and three RNA binding subunits and has been shown to bind and degrade RNA in vitro. Despite extensive studies on the eukaryotic exosome and on the proteins interacting with this complex, little information is yet available on the identification and function of archaeal exosome regulatory factors. 相似文献4.
5.
V. G. Neudatchin I. T. Obukhovsky Yu. F. Smirnov E. V. Tkalya 《Zeitschrift für Physik A Hadrons and Nuclei》1983,313(4):357-366
It is shown that in the 9q- and 12q-systems, i.e.,3He-3He and4He nuclei, the most energetically favourable colour magnetic types of symmetry are [f]cs=[621] and [f]cs=[822], which corresponds to the orbital configurationsS 5 P 4 [522] X andS 6 P 6 [623] X . The colour magnetic nucleon attraction associated with these configurations increases as the square of the nucleon number in the sequence2H,3He,4He, becoming quite strong in4He. This may provide a basis for explaining the “mysterious properties” of3He-3He and4He. However, with the further increase in A, the above effect drastically decreases. A qualitative calculation on the quark excitation spectrum for the3H-3He and4He nuclei is presented. The4He nucleus seems to possess some properties of a “quark magic nucleus”. The experimental situation is discussed. 相似文献
6.
Yu.F. Smirnov I.T. Obukhovsky Yu.M. Tchuvilsky V.G. Neudatchin 《Nuclear Physics A》1974,235(2):289-298
We have calculated the 01+ ground state and the 02+ and 03+ first excited states of 12C in the model of three α-particles whose interaction is described using a local attractive potential with forbidden states, which well reproduces the α-α scattering phases. The methods of projection of the states forbidden by the Pauli exclusion principle in a system of three composite particles are discussed. The results of the calculation show that the condition of orthogonality to the forbidden states is sufficient to prevent the system from collapse. The binding energy value obtained (15.06 MeV) is somewhat overestimated. This discrepancy seems to come from neglecting triple exchanges of nucleons of different α-particles and from the fact that the 12C real nucleus differs from the 3α system. 相似文献
7.
HARUN REŞIT YAZAR 《Pramana》2013,81(4):579-585
The sd-interacting boson approximation (sd-IBA) and the df-interacting boson approximation (df-IBA) can be related to each other and the states of the interacting boson approximation model can be identified with the fully symmetric states in the sdf interacting boson approximation model. A systematic study of the sdf-IBA model showed that the constructed Hamiltonian can successfully describe the strong octupole correlations in the deformed nuclei. We showed that the interacting boson approximation may account for many of these K π ?=?0+ states. It was found that the calculated energy spectra of the gadolinium isotopes agree quite well with the experimental data. The observed B(E2) values were also calculated and compared with the experimental data. 相似文献
8.
Vladimir G. Neudatchin Igor T. Obukhovsky Ludmila L. Sviridova Nikolai P. Yudin 《Central European Journal of Physics》2004,2(3):511-522
The pion momentum distributions (MDs) in four channels of virtual decay p→B+π, B = N, Δ, N
1/2-(1535), N
1/2+(1440) are calculated in two models, the microscopic model of 3
P
0 scalar q−q fluctuation with the pion as a composite q−q-system and the chiral semi-microscopic model of πq interaction with the pion as a structureless Goldstone boson. The results of the above models are similar for the baryon
states B = N, Δ, N
1/2-(1535) but are rather different for the Roper resonance N
1/2+(1440) which corresponds to excitation of two oscillator quanta in the nucleon. The experimental investigation of pion MDs
by means of the reaction of quasi-elastic knockout of pion by an electron of a few GeV energy p(e, e′ π)B may be very suitable for Jefferson Laboratory, Virginia (JLab). 相似文献
9.
10.
V. I. Kukulin I. T. Obukhovsky V. N. Pomerantsev A. Faessler 《Physics of Atomic Nuclei》2001,64(9):1667-1688
Arguments against the traditional Yukawa-type approach to NN intermediate-and shortrange interaction due to scalar-isoscalar and heavy-meson exchanges are presented. Instead of the Yukawa mechanism for intermediate-range attraction, some new approach based on the formation of a symmetric six-quark bag in the state |(0s)6[6]X, L=0〉 dressed owing to strong coupling to π, σ, and ρ fields is suggested. This new mechanism offers a strong intermediate-range attraction, which replaces effective σ exchange (or excitation of two isobars in the intermediate state) in traditional force models. A similar mechanism with the production of a vector ρ meson in the intermediate six-quark state is expected to lead to a strong short-range spin-orbit nonlocal interaction in the NN system, which may resolve the long-standing puzzle of the spin-orbit force in baryons and in two-baryon systems. The effective interaction in the NN channel provided by the new mechanism will be enhanced significantly if the partial restoration of chiral symmetry is assumed to occur inside the six-quark symmetric bag. A simple illustrative model is developed that demonstrates clearly how well the suggested new mechanism can reproduce NN data. Strong interrelations have been shown to exist between the proposed microscopic model and one-component Moscow NN potential developed by the authors previously and also with some hybrid models and the one-term separable Tabakin potential. The new implications of the proposed model for nuclear physics are discussed. 相似文献