Lithuanian Journal of Physics

Title

2025-08-13T09:54:43+03:00

2025-08-13T09:56:26+03:00

New generalized Hermite polynomials with three variables obtained via quantum optics method and their applications

2025-08-13T10:45:02+03:00

Special polynomials (e.g. Hermite polynomials) are very important for the development of physics and mathematics. As a further extension of ordinary Hermite polynomials, we introduce new generalized Hermite polynomials with three variables and find their generating functions using the operator ordering method in quantum optics. Also, some new operator identities and integral formulas are obtained. As applications, the normalization, Wigner functions and evolutions for certain quantum states are analytically presented. These analytical results can provide conveniences for numerically studying the properties and applications of such quantum states.

Second-order Rayleigh–Schrödinger perturbation theory for the GRASP2018 package: Three-particle Feynman diagram contribution to valence–valence correlations

2025-08-13T10:44:50+03:00

The method based on the second-order perturbation theory to identify the most important configuration state functions of various correlations is extended to include valence–valence correlations, which are described by the three-particle Feynman diagram. The extension presented in this work complements the core–valence, core, core–core and valence–valence correlations which were developed in a series of previous papers by G. Gaigalas, P. Rynkun, and L. Kitovienė. Whereas these valence–valence correlations are described by the three-particle Feynman diagram, additional developments to calculate the spin-angular parts of this diagram have been made to the program library librang of the Grasp. As an example of the application of the developed method, the atomic calculations of the energy structure for the Se III ion are presented. In the present work, this method was also used to select the most significant configuration state functions and to use this basis to solve the self-consistent field equations.

Radiography and radiotherapy of the simulated human tissue environment with high-energy protons: A theoretical study

2025-08-13T10:44:37+03:00

In this research, the diagnostic imaging and therapy of the environment of selected human tissues by the produced protons from fusion reactions have been simulated by using the Geant4 tool. As a result, the stopping power and range of protons with different energies in these tissues have been obtained. As an example, Bragg peaks caused by protons with energies of 60 to 150 MeV have been shown in breast tissue. Further, the penetration depth of protons, proton flux, and the secondary particle flux of neutrons and gamma with energies of 20 to 70 MeV (in the therapeutic energy range) have been investigated in the breast tissue. Finally, a comparison of the residual dose in breast tissue without a tumour and with a tumour at 60 MeV energy has been done. Therefore, with such simulations, calculations, and creative approaches, effective measures can be taken in the fields of proton imaging and proton therapy because proton radiography is a method that can be used to extract the maximum required information from different human tissues. Also, tumours located in different human tissues can be targeted and destroyed by using different energies of protons.

Lithuanian Journal of Physics

Title

Contents

New generalized Hermite polynomials with three variables obtained via quantum optics method and their applications

Second-order Rayleigh–Schrödinger perturbation theory for the GRASP2018 package: Three-particle Feynman diagram contribution to valence–valence correlations

Radiography and radiotherapy of the simulated human tissue environment with high-energy protons: A theoretical study