Ivan I Haysak | Uzhgorod National University (original) (raw)

Papers by Ivan I Haysak

Sov. J. Nucl. Phys. (Engl. Transl.); (United States), Feb 1, 1986

ABSTRACT

Uzhgorod National University's M-10 microtron is used for fundamental investigations of elect... more Uzhgorod National University's M-10 microtron is used for fundamental investigations of electrons, gamma\gammagamma-quanta, and neutron reactions with atomic nuclei, as well as for applied studies of the effects of irradiation on new technological materials and substances. Due to some modifications that the microtron has undergone over time, it has become possible to use it to generate neutrons.

Czechoslovak Journal of Physics, May 1, 2005

Based on the numeric solution of a system of coupled channels for vector mesons (S-and D-waves mi... more Based on the numeric solution of a system of coupled channels for vector mesons (S-and D-waves mixing) and for tensor mesons (P-and F-waves mixing) mass spectrum and wave functions of a family of vector mesons qq in triplet states are obtained. The calculations are performed using a well known Cornell potential with a mixed Lorentz-structure of the confinement term. The spin-dependent part of the potential is taken from the Breit-Fermi approach. The effect of singular terms of potential is considered in the framework of the perturbation theory and by a configuration interaction approach (CIA), modified for a system of coupled equations. It is shown that even a small contribution of the D-wave to be very important at the calculation of certain characteristics of the meson states.

arXiv (Cornell University), Jan 24, 2018

Experimental isomeric yield ratios for the 113 In(γ,n) 112m,g In reactions on the betatron B25/30... more Experimental isomeric yield ratios for the 113 In(γ,n) 112m,g In reactions on the betatron B25/30 bremsstrahlung gamma beam of energy range 12-25 MeV are measured. Effective cross-sections of (γ,n)-reactions with 112m In and 114m In isomers output are calculated. The Penfold-Leiss and Tikhonov methods are applied to solve the Volterra integral equation. The obtained experimental cross-sections are compared with theoretical calculations using the TALYS-1.6 code.

Physics Letters B, Feb 1, 1993

ABSTRACT Total cross sections for the reaction π+d→pp have been measured for incident pion energi... more ABSTRACT Total cross sections for the reaction π+d→pp have been measured for incident pion energies Tπ=26.5, 28.5, 30.5, 32.5 and 39.5 MeV. The data are in good agreement with previous experiments. There is some indication of a peculiarity in the energy dependence of the total cross section near incident pion energy Tπ=30 MeV.

Naukovij vìsnik Užgorodsʹkogo unìversitetu, Nov 23, 2022

Relevance. This paper describes the measurement of the cross sections of the fission and fragment... more Relevance. This paper describes the measurement of the cross sections of the fission and fragmentation reactions of a plutonium target irradiated with a series of protons characterized by an energy of 660 MeV at the Phazotron accelerator of the Joint Institute for Nuclear Research. Purpose. The experiment focuses on the determination of short-lived radionuclides. Methods. The experimental sample was measured in offline mode using gamma spectrometry with HPGe detector. The reaction rates of the formed residual nuclei were studied. The products of spallation reaction were determined with the help of the direct kinematics method. The DEIMOS32 software was used to process γ-spectra. Results. As a result of the interaction of nuclear elements with protons, nuclei were formed in the 239 Pu sample. Those nuclei were identified using the TJ02000321-V3 software. The reaction products were identified based on gamma energies, intensity and half-life after the measurement set. During the study of the gamma spectra determined for the irradiated plutonium target, it was possible to establish 50 gamma lines and reveal 31 nuclides by energy and half-life cycles from 14.4 m to 3.19 h. The measured nuclear reaction cross-sections can serve as reference data for theoretical simulations of the interaction of protons with 239 Pu and they can be a supplement to the nuclear databases. Conclusions. The obtained experimental result is compared with the simulation on MCNP 6.1. The data overall correspond to the expected range, but it still needs more evaluation. The next logical step is to search for primary products (mother nuclei) and compare the obtained experimental data with the results of computer simulations

The effect of irradiation by gamma quanta of a substance is caused by the absorbed dose. But in t... more The effect of irradiation by gamma quanta of a substance is caused by the absorbed dose. But in the experiment, it is possible to measure the exposure dose. The analysis of the results of sample iirradiation on electron accelerators is complicated by the non monochromatic character of the bremsstrahlung gamma. The procedure for measuring the absolute magnitude of the exposure dose and the calculation of the absorbed dose in the irradiation of samples of different structures by the electromagnetic bremsstrahlung are described.

arXiv (Cornell University), Jan 7, 2002

The influence of tensor forces on hyperfine splitting and decay widths of mesons are investigated... more The influence of tensor forces on hyperfine splitting and decay widths of mesons are investigated within the limits of quasirelativistic potential quark model. As the starting the system of the Rarita-Schwinger equations is used. We use a potential motivated by QCD with a mixed Lorentz structure.

Four Monte-Carlo codes where tested to simulate bremsstrahlung spectra for accelerated electron b... more Four Monte-Carlo codes where tested to simulate bremsstrahlung spectra for accelerated electron beams at the energy range 4–20 MeV. All four codes give the same shape of the spectrum, in which in addition to the bremsstrahlung part there are characteristic energy lines of the target atom and an annihilation line of 0.511 MeV caused by secondary processes of the photoelectric effect and of electron-positron pair production. The absolute values of the energy spectrum have close magnitudes but it requires a more thorough study.

Epj Web of Conferences, 2021

The neutron generation technique was tested on the microtron M-10 with an output electron beam of... more The neutron generation technique was tested on the microtron M-10 with an output electron beam of 8.7 MeV. Given the low energy that the microtron can provide to electrons, the bremsstrahlung induced photonuclear reaction 9 Be (γ, n), which has a low threshold, was chosen for neutron generation. Cobalt and indium targets were tested as activation detectors to estimate the neutron flux density. In the cobalt target, the isomeric state of 60m Co with an energy of 58.6 keV and a half-life of 10.5 minutes is well activated. Two well-known additional gamma lines of standard cobalt source permit to clarify the absolute value of the neutron flux. The activated indium target has four gamma lines bound to the 116m In isomer βdecaying with the half-life of 54.4 minutes, what is convenient for measurement of gamma spectrum. Despite the low energy of the output electron beam, at a beam intensity of 5 μA it is possible to obtain an almost isotropic neutron flux of 10 7 n/(s•cm 2).

Nuclear Physics, May 1, 1992

The total cross section of positive-pion absorption on carbon with a two-proton final state at pi... more The total cross section of positive-pion absorption on carbon with a two-proton final state at pion energies of 26-39 MeV has been measured. At a pion energy of 28.5 MeV some narrow structure exists in the energy dependence of the cross section. NUCLEAR REACTIONS : ' 2 C(7r +, pp)X; E =26-39 MeV; measured pion absorption Q(E) versus particle energy.

European Physical Journal C, Jun 1, 2001

The spin-spin mass splitting of light, heavy and mixed mesons are described within a good accurac... more The spin-spin mass splitting of light, heavy and mixed mesons are described within a good accuracy in the potential model with screened potential. We conclude that the long-distance part of the potential cannot be pure scalar and that a vector-scalar mixture is favoured. With the same parameters which gives correct average mass spectrum excellent spin-spin splittings of heavy quarkonia is obtained. The results are obtained by going beyond usually used perturbation method, namely using configuration interaction approach.

Acta Physica Polonica A

This paper presents the results of calculations of spectroscopic parameters of three-particle qua... more This paper presents the results of calculations of spectroscopic parameters of three-particle quantum systems, in particular the exotic helium atom (3 He 2+ , e, 3 H). These calculations were made within the framework of a nonrelativistic quantum-mechanical model for the problem of three bodies interacting according to the Coulomb's law. topics: quantum mechanical model, three-particle system

2017 IEEE 7th International Conference Nanomaterials: Application & Properties (NAP), 2017

Cu<inf>6</inf>PS<inf>5</inf>I-based thin films were deposited by nonreact... more Cu<inf>6</inf>PS<inf>5</inf>I-based thin films were deposited by nonreactive radio frequency magnetron sputtering onto silicate glass substrates. Optical transmission spectra of e-beam irradiated Cu<inf>6</inf>PS<inf>5</inf>I-based thin films were measured depending on electron fluence. With electron fluence increase the red shift of the short-wavelengt part of transmission spectra and interference maxima were observed. Urbach absorption edge and dispersion of refractive index for e-beam irradiated Cu<inf>6</inf>PS<inf>5</inf>I-based thin films were studied. Under the influence of e-beam irradiation the decrease of the energy pseudogap as well as the increase of the Urbach energy and refractive index were revealed. Influence of e-beam irradiation on the optical parameters and disordering processes in Cu<inf>6</inf>PS<inf>5</inf>I-based thin films was analyzed.

2020 21st International Scientific Conference on Electric Power Engineering (EPE), 2020

This paper shows the results from the experiment that was done in JINR (Joint Institute for Nucle... more This paper shows the results from the experiment that was done in JINR (Joint Institute for Nuclear Research) Dubna. Thorium foil between two aluminum foils was irradiated inside Phasotron with 100 MeV protons. As a result - gamma spectra was obtained from the Th and aluminum foils and residual nuclei cross-sections were evaluated from the reaction. Also there was made a simulation analysis of the beam distribution inside the Th foil and particle escape from the target. The experimental cross-sections were compared with calculations made in Monte-Carlo simulation (MCNP 6.1).

Scientific Herald of Uzhhorod University.Series Physics

In this work the results of our studies of the effect of high-energy irradiation of the nominally... more In this work the results of our studies of the effect of high-energy irradiation of the nominally undoped Sn2P2S6 crystals grown by vapor-transport technique on their dielectric spectra are presented. The oriented (polar cut) samples were irradiated with gamma-rays with an average energy ~20 MeV with various exposition times (from 15 to 45 min). It was found that the obtained variations in dielectric spectra, caused by the irradiation, are unstable, and demonstrate slow changes: the measurements performed with time intervals of about 24 hours show that the relaxation to the initial state is reached during 2-3 weeks. Besides, an analysis of the dielectric spectra leads to the following conclusions: gamma-radiation stimulates an increase of the dielectric constant ε&#39; at low frequencies (20-100 Hz), measured immediately after pre-illumination, approximately in five times. The dielectric losses also increase in 1.5-2 times. Most likely this occurs due to an appearance of additional charged defects, movements of which in measuring field produces an additional contribution to the ε&#39; values. These charged defects produce stronger impacts at low frequencies, indicating on their relatively large size and/or their low movability, i.e. their localization. The measured dielectric spectra were compared with the same results obtained after radiation with fast electrons and intense white light. After lightening, as well as beta-irradiation, we observed decreasing of the value of low-frequency (~10 kHz) dielectric constant ε0 with time. In contrast, gamma-radiation leads to increasing of the dielectric constant, and subsequent relaxation with saturation after ~40 hours. The time evolution of the efficient parameters of the dielectric dispersion (dielectric contribution Δε, relaxation time  and diffusion parameter ) were estimated. After irradiation by gamma-rays and fast electrons is observed a decreasing of the Δε, α and time constant values. After lighting is observed more complicate relaxation when these parameters initially are rising, and then are falling. This indicates that the white-light lightening has a stronger effect on the dielectric properties of the Sn2P2S6 crystals as compared with gamma- and beta-radiation. The results of our experiments with preliminary irradiated by gamma-rays, fast electrons or intense white light indicate on substantially different mechanisms of the induced defects, and relatively slow subsequent relaxation of the dielectric parameters. Note that variations of the optical density induced by the radiation were did not marked. Keywords: dielectric spectra, ferroelectric, β and γ irradiation.

Journal of Physical Studies

Sov. J. Nucl. Phys. (Engl. Transl.); (United States), Feb 1, 1986

ABSTRACT

Uzhgorod National University's M-10 microtron is used for fundamental investigations of elect... more Uzhgorod National University's M-10 microtron is used for fundamental investigations of electrons, gamma\gammagamma-quanta, and neutron reactions with atomic nuclei, as well as for applied studies of the effects of irradiation on new technological materials and substances. Due to some modifications that the microtron has undergone over time, it has become possible to use it to generate neutrons.

Czechoslovak Journal of Physics, May 1, 2005

Based on the numeric solution of a system of coupled channels for vector mesons (S-and D-waves mi... more Based on the numeric solution of a system of coupled channels for vector mesons (S-and D-waves mixing) and for tensor mesons (P-and F-waves mixing) mass spectrum and wave functions of a family of vector mesons qq in triplet states are obtained. The calculations are performed using a well known Cornell potential with a mixed Lorentz-structure of the confinement term. The spin-dependent part of the potential is taken from the Breit-Fermi approach. The effect of singular terms of potential is considered in the framework of the perturbation theory and by a configuration interaction approach (CIA), modified for a system of coupled equations. It is shown that even a small contribution of the D-wave to be very important at the calculation of certain characteristics of the meson states.

arXiv (Cornell University), Jan 24, 2018

Experimental isomeric yield ratios for the 113 In(γ,n) 112m,g In reactions on the betatron B25/30... more Experimental isomeric yield ratios for the 113 In(γ,n) 112m,g In reactions on the betatron B25/30 bremsstrahlung gamma beam of energy range 12-25 MeV are measured. Effective cross-sections of (γ,n)-reactions with 112m In and 114m In isomers output are calculated. The Penfold-Leiss and Tikhonov methods are applied to solve the Volterra integral equation. The obtained experimental cross-sections are compared with theoretical calculations using the TALYS-1.6 code.

Physics Letters B, Feb 1, 1993

ABSTRACT Total cross sections for the reaction π+d→pp have been measured for incident pion energi... more ABSTRACT Total cross sections for the reaction π+d→pp have been measured for incident pion energies Tπ=26.5, 28.5, 30.5, 32.5 and 39.5 MeV. The data are in good agreement with previous experiments. There is some indication of a peculiarity in the energy dependence of the total cross section near incident pion energy Tπ=30 MeV.

Naukovij vìsnik Užgorodsʹkogo unìversitetu, Nov 23, 2022

Relevance. This paper describes the measurement of the cross sections of the fission and fragment... more Relevance. This paper describes the measurement of the cross sections of the fission and fragmentation reactions of a plutonium target irradiated with a series of protons characterized by an energy of 660 MeV at the Phazotron accelerator of the Joint Institute for Nuclear Research. Purpose. The experiment focuses on the determination of short-lived radionuclides. Methods. The experimental sample was measured in offline mode using gamma spectrometry with HPGe detector. The reaction rates of the formed residual nuclei were studied. The products of spallation reaction were determined with the help of the direct kinematics method. The DEIMOS32 software was used to process γ-spectra. Results. As a result of the interaction of nuclear elements with protons, nuclei were formed in the 239 Pu sample. Those nuclei were identified using the TJ02000321-V3 software. The reaction products were identified based on gamma energies, intensity and half-life after the measurement set. During the study of the gamma spectra determined for the irradiated plutonium target, it was possible to establish 50 gamma lines and reveal 31 nuclides by energy and half-life cycles from 14.4 m to 3.19 h. The measured nuclear reaction cross-sections can serve as reference data for theoretical simulations of the interaction of protons with 239 Pu and they can be a supplement to the nuclear databases. Conclusions. The obtained experimental result is compared with the simulation on MCNP 6.1. The data overall correspond to the expected range, but it still needs more evaluation. The next logical step is to search for primary products (mother nuclei) and compare the obtained experimental data with the results of computer simulations

The effect of irradiation by gamma quanta of a substance is caused by the absorbed dose. But in t... more The effect of irradiation by gamma quanta of a substance is caused by the absorbed dose. But in the experiment, it is possible to measure the exposure dose. The analysis of the results of sample iirradiation on electron accelerators is complicated by the non monochromatic character of the bremsstrahlung gamma. The procedure for measuring the absolute magnitude of the exposure dose and the calculation of the absorbed dose in the irradiation of samples of different structures by the electromagnetic bremsstrahlung are described.

arXiv (Cornell University), Jan 7, 2002

The influence of tensor forces on hyperfine splitting and decay widths of mesons are investigated... more The influence of tensor forces on hyperfine splitting and decay widths of mesons are investigated within the limits of quasirelativistic potential quark model. As the starting the system of the Rarita-Schwinger equations is used. We use a potential motivated by QCD with a mixed Lorentz structure.

Four Monte-Carlo codes where tested to simulate bremsstrahlung spectra for accelerated electron b... more Four Monte-Carlo codes where tested to simulate bremsstrahlung spectra for accelerated electron beams at the energy range 4–20 MeV. All four codes give the same shape of the spectrum, in which in addition to the bremsstrahlung part there are characteristic energy lines of the target atom and an annihilation line of 0.511 MeV caused by secondary processes of the photoelectric effect and of electron-positron pair production. The absolute values of the energy spectrum have close magnitudes but it requires a more thorough study.

Epj Web of Conferences, 2021

The neutron generation technique was tested on the microtron M-10 with an output electron beam of... more The neutron generation technique was tested on the microtron M-10 with an output electron beam of 8.7 MeV. Given the low energy that the microtron can provide to electrons, the bremsstrahlung induced photonuclear reaction 9 Be (γ, n), which has a low threshold, was chosen for neutron generation. Cobalt and indium targets were tested as activation detectors to estimate the neutron flux density. In the cobalt target, the isomeric state of 60m Co with an energy of 58.6 keV and a half-life of 10.5 minutes is well activated. Two well-known additional gamma lines of standard cobalt source permit to clarify the absolute value of the neutron flux. The activated indium target has four gamma lines bound to the 116m In isomer βdecaying with the half-life of 54.4 minutes, what is convenient for measurement of gamma spectrum. Despite the low energy of the output electron beam, at a beam intensity of 5 μA it is possible to obtain an almost isotropic neutron flux of 10 7 n/(s•cm 2).

Nuclear Physics, May 1, 1992

The total cross section of positive-pion absorption on carbon with a two-proton final state at pi... more The total cross section of positive-pion absorption on carbon with a two-proton final state at pion energies of 26-39 MeV has been measured. At a pion energy of 28.5 MeV some narrow structure exists in the energy dependence of the cross section. NUCLEAR REACTIONS : ' 2 C(7r +, pp)X; E =26-39 MeV; measured pion absorption Q(E) versus particle energy.

European Physical Journal C, Jun 1, 2001

The spin-spin mass splitting of light, heavy and mixed mesons are described within a good accurac... more The spin-spin mass splitting of light, heavy and mixed mesons are described within a good accuracy in the potential model with screened potential. We conclude that the long-distance part of the potential cannot be pure scalar and that a vector-scalar mixture is favoured. With the same parameters which gives correct average mass spectrum excellent spin-spin splittings of heavy quarkonia is obtained. The results are obtained by going beyond usually used perturbation method, namely using configuration interaction approach.

Acta Physica Polonica A

This paper presents the results of calculations of spectroscopic parameters of three-particle qua... more This paper presents the results of calculations of spectroscopic parameters of three-particle quantum systems, in particular the exotic helium atom (3 He 2+ , e, 3 H). These calculations were made within the framework of a nonrelativistic quantum-mechanical model for the problem of three bodies interacting according to the Coulomb's law. topics: quantum mechanical model, three-particle system

2017 IEEE 7th International Conference Nanomaterials: Application & Properties (NAP), 2017

Cu<inf>6</inf>PS<inf>5</inf>I-based thin films were deposited by nonreact... more Cu<inf>6</inf>PS<inf>5</inf>I-based thin films were deposited by nonreactive radio frequency magnetron sputtering onto silicate glass substrates. Optical transmission spectra of e-beam irradiated Cu<inf>6</inf>PS<inf>5</inf>I-based thin films were measured depending on electron fluence. With electron fluence increase the red shift of the short-wavelengt part of transmission spectra and interference maxima were observed. Urbach absorption edge and dispersion of refractive index for e-beam irradiated Cu<inf>6</inf>PS<inf>5</inf>I-based thin films were studied. Under the influence of e-beam irradiation the decrease of the energy pseudogap as well as the increase of the Urbach energy and refractive index were revealed. Influence of e-beam irradiation on the optical parameters and disordering processes in Cu<inf>6</inf>PS<inf>5</inf>I-based thin films was analyzed.

2020 21st International Scientific Conference on Electric Power Engineering (EPE), 2020

This paper shows the results from the experiment that was done in JINR (Joint Institute for Nucle... more This paper shows the results from the experiment that was done in JINR (Joint Institute for Nuclear Research) Dubna. Thorium foil between two aluminum foils was irradiated inside Phasotron with 100 MeV protons. As a result - gamma spectra was obtained from the Th and aluminum foils and residual nuclei cross-sections were evaluated from the reaction. Also there was made a simulation analysis of the beam distribution inside the Th foil and particle escape from the target. The experimental cross-sections were compared with calculations made in Monte-Carlo simulation (MCNP 6.1).

Scientific Herald of Uzhhorod University.Series Physics

In this work the results of our studies of the effect of high-energy irradiation of the nominally... more In this work the results of our studies of the effect of high-energy irradiation of the nominally undoped Sn2P2S6 crystals grown by vapor-transport technique on their dielectric spectra are presented. The oriented (polar cut) samples were irradiated with gamma-rays with an average energy ~20 MeV with various exposition times (from 15 to 45 min). It was found that the obtained variations in dielectric spectra, caused by the irradiation, are unstable, and demonstrate slow changes: the measurements performed with time intervals of about 24 hours show that the relaxation to the initial state is reached during 2-3 weeks. Besides, an analysis of the dielectric spectra leads to the following conclusions: gamma-radiation stimulates an increase of the dielectric constant ε&#39; at low frequencies (20-100 Hz), measured immediately after pre-illumination, approximately in five times. The dielectric losses also increase in 1.5-2 times. Most likely this occurs due to an appearance of additional charged defects, movements of which in measuring field produces an additional contribution to the ε&#39; values. These charged defects produce stronger impacts at low frequencies, indicating on their relatively large size and/or their low movability, i.e. their localization. The measured dielectric spectra were compared with the same results obtained after radiation with fast electrons and intense white light. After lightening, as well as beta-irradiation, we observed decreasing of the value of low-frequency (~10 kHz) dielectric constant ε0 with time. In contrast, gamma-radiation leads to increasing of the dielectric constant, and subsequent relaxation with saturation after ~40 hours. The time evolution of the efficient parameters of the dielectric dispersion (dielectric contribution Δε, relaxation time  and diffusion parameter ) were estimated. After irradiation by gamma-rays and fast electrons is observed a decreasing of the Δε, α and time constant values. After lighting is observed more complicate relaxation when these parameters initially are rising, and then are falling. This indicates that the white-light lightening has a stronger effect on the dielectric properties of the Sn2P2S6 crystals as compared with gamma- and beta-radiation. The results of our experiments with preliminary irradiated by gamma-rays, fast electrons or intense white light indicate on substantially different mechanisms of the induced defects, and relatively slow subsequent relaxation of the dielectric parameters. Note that variations of the optical density induced by the radiation were did not marked. Keywords: dielectric spectra, ferroelectric, β and γ irradiation.

Journal of Physical Studies