No abstract available

[en] In connection with the opening possibility of obtaining the beams of_λ³H hypernuclei with good characteristics, in particular, at the Dubna accelerating complex Synchrophasotron-Nuclotron of JINR the diffraction approach is developed to perform both the exact numerical and general theoretical analysis of various integral cross sections of the Coulomb and nuclear interactions of incident hypertritons with absorbing nuclei at high energies. As follows from our calculations, the internal structure of the _λ³H hypernucleus as well as the phenomena of double and triple scattering can essentially influence on the value of the integral cross sections of diffraction-nucleus interaction and on the cross section of the Coulomb two-fragment dissociation of _λ³H at high energies. The allowance for finite range nuclear forces between Λ-hyperon and deuteron cluster can lead to a change in the integral cross sections by 10-15%. The noticeable sensitivity of the cross sections to variations of the hypertriton binding energy with respect to the disintegration into a Λ-hyperon and a deuteron (especially in the case of the _λ³H Coulomb dissociation is revealed. The essential effect of the triple scattering on the value of the total cross section of the _λ³H diffraction interaction with nuclei is established. The allowance for the finite range of the n-p forces in the deuteron cluster leads to the increase of the total cross section by ∼ 10%. It is shown that the Glauber approximation is only valid in the case of the lightest target nuclei. (author)

[en] The (t, ³He)-reaction is an interesting tool for the study of spin-isospin excitations in nuclei. Safety problems in the handling of tritium have sofar precluded its widespread use and have even led to the use of secondary triton beams. The feasibility of providing accelerated triton beams for experiments, with the constraint that no additional safety measures for the use of tritium are needed, is discussed. It is concluded that with the existing source triton beams with an intensity up to 10⁷ pps and an energy up to 65 MeV per nucleon can be delivered; installation of a dedicated high efficiency ion source and a better transmission in the low energy beam lines will give a tenfold increase in intensity. These intensities require a tritium consumption of about 1.5 MBq per week

No abstract available

[en] The predominant effect of thermal atom irradiation on solid molecules is saturation of their aromatic functions. Only low levels of tritium exchange is observed for alipathic solids. In contrast, liquids whose frozen surface can be rendered somewhat mobile at appropriate temperatures exhibit more exchange than addition. The rank order of effectiveness of several metals in promoting exchange/addition appears similar to the rank order for heterogeneous catalytic hydrogeneration. (author). 3 refs.; 8 figs.; 1 tab

No abstract available

[en] The role of deuteron asymptotic D to S normalization rati η^D on the calculation of triton observables is emphasized. Studying the new correlations among triton asymptotic normalizations and η^D a new estimate of triton asymptotic normalizations C_S and C_D is made: C_ζ=1.85+-0.04, C_D/C_S=0.0463+-0.0013, for η^D=0.0271 (4), and C_D/C_S η^D=1.71+-0.04. (Author)

[en] An attempt was made for the explanation of experimental angular distribution of p₀-group at Esub(t)=0.9 MeV by two different approaches. a) theoretical distribution in PWBA approximation, with the inclusion of Coulomb distorsions, according to four vertex diagram, and b) mechanism of double-stripping, according to two vertex diagram, calculated by DWBA method. (author)

[en] Repulsive core effects in two-nucleon transfer reactions are investigated referring to the (t,p) stripping reactions. The form factor for the (t,p) stripping reactions is calculated using a Tabakin potential for the neutron-proton interaction. Two different cases are considered by taking for the repulsive and attractive parts of the Tabakin potential a Yamaguchi type or Breit et al. type parameters. It is found that the repulsive core effects are important and should be taken into account to extract reasonable spectroscopic factors

[en] Because of discrepancies in previous measurements of the D(t,α)n reactions at low energies, we have developed a low-energy fusion cross-section facility (LEFCS) to remeasure the D(t,α) and other few-nucleon reactions. The experimental equipment features a windowless cryogenic target, a precision beam-intensity calorimenter, a 10 to 120 keV accelerator producing negative tritium ions, an accurate target gas flow and temperature system, and a tritium gas-handling system. The target density and geometry are calibrated with the D(p,p)D reaction using 10-MeV protons from the Los Alamos Van-de-Graaff. Presented are 16 D(t,α)n total cross sections from 8.3 to 78.1 keV equivalent deuteron energy. The relative error is 0.5% and the absolute error is 1.4% for most energies. For the lowest energy both uncertainties rise to about 4.7%. We will also attempt to measure the D(t,γ)⁵He cross section. We have made preliminary background studies with the LEFCS target and a bismuth germanate counter with encouraging results