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A new approach towards solving quantum scattering problems with a short-range interaction and repulsive Coulomb interaction is introduced on the base of the Coulomb wave-packet formalism. The formalism allows to construct a finite-dimensional spectral expansion for the pure Coulomb resolvent and the resolvent for the Coulomb distorted short-range interaction as well. The above Coulomb wave-packet states can be approximated via the so-called complex-range Gaussian basis which is shown to be very convenient for practical calculations in continuum. As a result, the off-mass-shell elements of the Coulomb-nuclear t-matrix are found in a wide energy region from diagonalisation procedures for the total and Coulomb Hamiltonian matrices on the basis presented. The method is illustrated by few examples for calculations of partial amplitudes for local potentials and non-local coupled-channel interaction caused by an intruder state. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

A diagnostic application of gamma rays emitted in 6Li+D and 6Li+T nuclear reactions induced by admixing a small amount of 6Li in DT fusion plasma is investigated. It is shown that the reaction-produced monochromatic gamma quanta with energies E(gamma)=0.429, 0.478, and 0.981 MeV can be used for ion temperature measurements in DT plasma. The proposed measurements are expected to be essentially independent of the plasma density and its local fluctuations. The required reaction cross sections and the Maxwellian rate parameters of the 6Li+T gamma-ray production are calculated within a realistic nuclear model.