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1.
A simple method for calculating the amplitude and the cross section for the Coulomb breakup of a light nucleus into two fragments in the field of a heavy ion at relativistic collision energies is proposed on the basis of time-dependent perturbation theory. It is shown that the resulting amplitude for the process in question has a correct nonrelativistic limit. The contribution of the longitudinal component of the Coulomb field of a heavy ion tends to zero in the ultrarelativistic limit. A specific implementation of the method is demonstrated by taking the example of the Coulomb breakup reaction 208Pb(8B, 7Bep)208Pb at various collision energies. The results are found to be in agreement with experimental data. 相似文献
2.
L. D. Blokhintsev V. O. Eremenko B. F. Irgaziev Yu. V. Orlov 《Bulletin of the Russian Academy of Sciences: Physics》2011,75(4):505-510
3H and 3He nuclei are considered in a two-body model (3H = n + d; 3He = p + d). Two independent approaches are used: in the first, interaction is described by the folding potential, while NN potentials are taken in the Hulthen form with allowance for violations of isotopic invariance. The second approach features
phenomenological Hulthen and Yukawa Nd potentials used as Nd interaction. In both approaches, the binding energies, vertex constants, and asymptotic normalization coefficients in the
N+d channel are calculated. 相似文献
3.
R. G. Pizzone C. Spitaleri A. M. Mukhamedzhanov L. D. Blokhintsev C. A. Bertulani B. F. Irgaziev M. La Cognata L. Lamia S. Romano 《Few-Body Systems》2011,50(1-4):319-321
The widths of the spectator momentum distributions in several nuclei, which have been used as Trojan Horses, have been obtained as a function of the transferred momentum. Applications of Trojan Horse method will also be discussed. 相似文献
4.
L. D. Blokhintsev V. O. Eremenko B. F. Irgaziev Yu. V. Orlov 《Bulletin of the Russian Academy of Sciences: Physics》2008,72(6):811-816
The characteristics of bound states of hypernuclei were calculated in [1] in a wide range of mass numbers within the potential model for three different potentials. In this study, the phase shifts and low-energy parameters for scattering of Λ hyperons from core nuclei, considered in [1], have been calculated for the same potentials. The calculated scattering lengths and effective radii are compared with their values found in [1] on the basis of the data on the binding energies and vertex constants of hypernuclei. 相似文献
5.
La Cognata M Spitaleri C Mukhamedzhanov AM Irgaziev B Tribble RE Banu A Cherubini S Coc A Crucillà V Goldberg VZ Gulino M Kiss GG Lamia L Mrazek J Pizzone RG Puglia SM Rapisarda GG Romano S Sergi ML Tabacaru G Trache L Trzaska W Tumino A 《Physical review letters》2008,101(15):152501
The 18O(p,alpha)15N reaction is of primary importance in several astrophysical scenarios, including fluorine nucleosynthesis inside asymptotic giant branch stars as well as oxygen and nitrogen isotopic ratios in meteorite grains. Thus the indirect measurement of the low energy region of the 18O(p,alpha)15N reaction has been performed to reduce the nuclear uncertainty on theoretical predictions. In particular the strength of the 20 and 90 keV resonances has been deduced and the change in the reaction rate evaluated. 相似文献
6.
Andrew G McDonald Sinéad Boyce Gerard P Moss Henry BF Dixon Keith F Tipton 《BMC biochemistry》2007,8(1):14
Background
We describe the database ExplorEnz, which is the primary repository for EC numbers and enzyme data that are being curated on behalf of the IUBMB. The enzyme nomenclature is incorporated into many other resources, including the ExPASy-ENZYME, BRENDA and KEGG bioinformatics databases. 相似文献7.
L. D. Blokhintsev V. O. Eremenko B. F. Irgaziev Yu. V. Orlov 《Bulletin of the Russian Academy of Sciences: Physics》2007,71(3):408-414
The vertex constants, asymptotic normalization coefficients, and mean-square radii for a number of Λ hypernuclei have been calculated in a wide range of mass numbers. Interaction of a Λ hyperon with a core nucleus was described by the Woods-Saxon, Hultén, and Yukawa potentials. Geometric parameters of the Woods-Saxon potential were taken from the data in the literature, and the interaction force was fitted to the experimental binding energy of the ground state of this hypernucleus. The parameters of the Hulthén and Yukawa potentials were chosen so as to reproduce simultaneously the binding energy of the hyperon and its mean-square radius calculated with the Woods-Saxon potential. Within the effective-radius approximation, the low-energy parameters for hyperon scattering by the core nucleus are expressed in terms of vertex constants and the numerical values of these parameters are determined. 相似文献
8.
Yu. V. Orlov B. F. Irgaziev 《Bulletin of the Russian Academy of Sciences: Physics》2008,72(11):1539-1543
The regularization of the normalization integral for the resonant wave function, proposed by Zeldovich, is valid only when |Req res| > |Imq res|. A new normalization procedure is proposed and implemented, which is valid when this condition fails. First, an arbitrarily normalized vertex function g(k) is calculated using the formula with the potential V(r) in the integrand. This Fourier integral converges for a potential with the asymptotics V(r) → constr ?n exp(?μr) if |Imq res| < μ/2. Then the function g(k) is normalized using the generalized normalization rule, which is independent of the resonance pole position. The proposed method is approved by the example of calculation for a virtual triton. 相似文献
9.
L. D. Blokhintsev B. F. Irgaziev A. M. Mukhamedzhanov A. N. Safronov A. A. Safronov 《Bulletin of the Russian Academy of Sciences: Physics》2008,72(3):295-300
N/D equations taking into account the Coulomb interaction effects are used to consider the phase analysis data on 3He4He scattering and determine the nuclear vertex constants for the 7Be ? 3He4He vertex, where the beryllium nucleus is in the ground (3/2?) or first excited (1/2?) states. Information about the asymptotic normalization coefficients of the wave functions of the 7Be nucleus in the noted states is derived. The data obtained are used to calculate the astrophysical S factor for the 4He(3He, γ)7Be reaction. 相似文献
10.
B. F. Irgaziev A. M. Mukhamedzhanov Yu. V. Orlov 《Bulletin of the Russian Academy of Sciences: Physics》2009,73(6):773-777
A method has been developed for calculating the off-shell wave function by solving the inhomogeneous Schrödinger equation with allowance for the nuclear and Coulomb interactions. The off-shell wave function makes it possible to construct the off-shell scattering amplitude in order to solve the problems for three or more particles. An important application of the method is the Trojan Horse calculations of nuclear reactions that are important in nuclear astrophysics. Specific calculations are performed for neutron and proton scattering on the 7Be nucleus. The Woods-Saxon potential is used and the spin-orbital interaction is taken into account. 相似文献