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21.
E. S. Konobeevski S. V. Zuyev A. A. Kasparov V. I. Kukulin V. M. Lebedev M. V. Mordovskoy V. N. Pomerantsev A. V. Spassky 《Physics of Atomic Nuclei》2018,81(5):595-603
Data obtained in recent years for the neutron–neutron scattering length in nd and dd breakup reactions are analyzed. Serious discrepancies between experimental data from different studies may be explained by the effect of three-nucleon forces depending on the velocity of separation of a neutron–neutron pair and a charged fragment. It is shown that the data under analysis can be approximated by a smooth curve representing the dependence of the scattering length on the parameter R, which determines the fragment-separation distance after a fixed time. This dependence makes it possible to obtain the scatteringlength value for R→∞—that is, in the absence of the effect of three-nucleon forces. 相似文献
22.
O. A. Rubtsova V. I. Kukulin V. N. Pomerantsev 《Bulletin of the Russian Academy of Sciences: Physics》2009,73(6):750-755
A new approach to describe the dynamics of nuclear reactions is proposed. The approach is based on the discretization of the total Hamiltonian continuum. The usage of the special stationary wave-packet basis makes it possible to reduce the scattering integral equations to matrix ones. The energy singularities of the initial equation kernels are smoothed by the averaging over discretization intervals. The approach is highly universal and allows one to properly take into account various exchange processes. In addition, the wave-packet technique makes it possible to construct effective optical potentials of interaction between composite nuclei. 相似文献
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24.
The results of an experiment on muon catalyzed dd-fussion in HD gas are presented. The experiment was performed at the muon beam of PSI using a high-pressure ionization chamber
filled with pure HD-gas of low D2 concentration on the level 1%, at temperatures 50, 150 and 300 K. The non-resonant character of ddμ-molecule formation on HD molecules was confirmed by measuring the ratio of yields of the two ddμ-fusion channels, R=Y(3He,n)/Y(3H,p), which proved to be close to unity. The ddμ formation rate was found to vary from λddμ-HD=0.05· 106 s-1 at T=50 K to λddμ-HD=0.12· 106 s-1 at T=300 K, in agreement with the theoretical prediction. A prominent peak at t<60 ns was observed in the time spectrum of fusion neutrons indicating a resonant contribution of ddμ formation from epithermal dμ atoms.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
25.
N. N. Barashkov M. E. Globus A. A. Ishchenko I. P. Krainov T. M. Murav'eva V. V. Pomerantsev V. V. Popov O. K. Rossikhina V. G. Senchishin A. V. Sidel'nikova V. M. Shershukov 《Journal of Applied Spectroscopy》1991,55(6):1193-1205
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 55, No. 6, pp. 906–918, December, 1991. 相似文献
26.
Moiseeva I. D. Kurylev A. Yu. Pomerantsev V. M. Tubolkin A. F. 《Russian Journal of Applied Chemistry》2002,75(11):1883-1884
A novel electrolytic method for preparing the catalyst (active aluminum oxide) for melamine synthesis and a process for catalytic synthesis of melamine from urea are proposed. 相似文献
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28.
Oxana Rodionova Alexey Pomerantsev Lars Houmøller Alexey Shpak Oleg Shpigun 《Analytical and bioanalytical chemistry》2010,397(5):1927-1935
Application of near-infrared (NIR) measurements together with chemometric data processing is widely used for counterfeit drug
detection. The most difficult counterfeits to detect are the “high quality fakes”, which have the proper composition but are
produced in violation of technological regulations by underground manufacturers. This study uses such forgeries and addresses
important issues. The first is the possibility of applying the NIR/chemometric approach to the detection of injectable formulations
of drugs (in this case dexamethasone), which are aqueous solutions with low concentration of active ingredients, directly
in the closed ampoules. The second issue is the comparison of NIR/chemometric conclusions with detailed chemical analysis. 相似文献
29.
V.I. Kukulin P. Grabmayr Kh.U. Abraamyan H. Clement V.N. Pomerantsev 《Annals of Physics》2010,325(6):1173-1189
Numerous theoretical and experimental arguments in favor of the generation of intermediate σ-dressed dibaryon in NN interaction at middle and short distances are presented. We argue that this intermediate dibaryon should be responsible for the strong middle-range attraction and the short-range repulsion in the NN interaction, and also for the short-range correlations in nuclei. The suggested mechanism for the σ-dressing of the dibaryon is identical to that which explains the Roper-resonance structure, its dominant decay mode and its extraordinary low mass. It is arguing that the (partial) chiral symmetry restoration effects, common for the Roper resonance and dressed dibaryon, are responsible for strong renormalizing of their masses and widths and the observed σ-meson mass and decay width as well. The new experimental data on 2π-production in the scalar-isoscalar channel produced in pn- and pd-collisions and recent data on γγ correlations in pC and dC scattering in the GeV region seems to corroborate the existence of the σ-dressed dibaryon in two- and three-nucleon interactions. A similar transformation mechanism from the glue to the scalar field can be valid also in some J/Ψ decays and in enormous σ-meson production in central pp collisions at high energies. 相似文献
30.
V. I. Kukulin V. N. Pomerantsev O. A. Rubtsova 《Theoretical and Mathematical Physics》2007,150(3):403-424
We generalize the wave-packet continuum discretization method previously developed for the scattering problem to the three-body
system. For each asymptotic channel, we construct a basis of three-body wave packets given by square-integrable functions.
We show that the projections of the channel resolvents on the subspace of three-body wave packets are determined by diagonal
matrices, whose eigenvalues we find explicitly. We express the amplitudes of 2→2 processes explicitly in terms of “wave-packet”
finite-dimensional projections of the full resolvent. To illustrate our formalism, we calculate the differential cross section
of elastic deuteron scattering on a heavy nucleus above the three-body breakup threshold and the s-wave quartet (n-d)-scattering
amplitude. The results of the calculations agree well with the results obtained by other methods. In terms of complexity,
the proposed scheme for solving the three-body scattering problem is comparable to solving a similar problem for bound states.
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Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 150, No. 3, pp. 473–497, March, 2007. 相似文献