Nucleon-nucleon interaction in the JJ-matrix inverse scattering approach and few-nucleon systems

The nucleon-nucleon interaction is constructed by means of the $J$-matrix version of inverse scattering theory. Ambiguities of the interaction are eliminated by postulating tridiagonal and quasi-tridiagonal forms of the potential matrix in the oscillator basis in uncoupled and coupled waves, respectively. The obtained interaction is very accurate in reproducing the $NN$ scattering data and deuteron properties. The interaction is used in the no-core shell model calculations of $^3$H and $^4$He nuclei. The resulting binding energies of $^3$H and $^4$He are very close to experimental values.Comment: Text is revised, new figures and references adde

Application of the JJ-matrix Method to Faddeev-Merkuriev equation: beyond pseudostates

A version of the $J$-matrix method for solving numerically the three-body Faddeev-Merkuriev differential equations is proposed. This version allows to take into account the full spectrum of the two-body Coulomb subsystem. As a result, a discrete analog of the Lippmann-Schwinger equation is obtained which allows to interpret correctly the three-body wave function in two-body domains. The scheme is applied to calculations of the fully resolved absolute differential cross sections for the He$(e,2e)$He$^+$ and He$(e,3e)$He$^{++}$ reactions at small energy and momentum transfers. The results are in good agreement with the experiment both in shape and in absolute value.Comment: 22 pages, 7 figure

Phytohormonal regulation of in vitro formation of wheat androgenic structures

This research is devoted to developing a method of phytohormonal regulation of in vitro formation of a certain type of wheat androgenic structures. Using the method of ELISA it was shown that the induction of certain sporophytic morphogenesis pathway in vitro of anther haploid cells - microspores depends on both the content of endogenous auxin IAA in anthers before inoculating them onto induction medium, and the concentration of exogenous auxin 2,4-D in this medium. The obtained data confirms the principle possibility of regulation of ways of getting androgenic regenerants in vitro by selecting the optimal balance of endogenous and exogenous auxin

Inverse scattering J-matrix approach to nucleon-nucleus scattering and the shell model

The $J$-matrix inverse scattering approach can be used as an alternative to a conventional $R$-matrix in analyzing scattering phase shifts and extracting resonance energies and widths from experimental data. A great advantage of the $J$-matrix is that it provides eigenstates directly related to the ones obtained in the shell model in a given model space and with a given value of the oscillator spacing $\hbar\Omega$. This relationship is of a particular interest in the cases when a many-body system does not have a resonant state or the resonance is broad and its energy can differ significantly from the shell model eigenstate. We discuss the $J$-matrix inverse scattering technique, extend it for the case of charged colliding particles and apply it to the analysis of $n\alpha$ and $p\alpha$ scattering. The results are compared with the No-core Shell Model calculations of $^5$He and $^5$Li.Comment: Some text is added following suggestions of a journal refere