arXiv subjects

Ihor Kadenko

Publications and source records attributed to Ihor Kadenko.

3 recordsLinked to original sources

arXiv2026

Observation of hidden nuclear reactions on fast neutron-irradiated Lu isotopes

Some nuclear reaction channels may not be easily identified, but they can still contribute to very important characteristics like nuclear reaction cross-sections, isomeric yields, etc. The dineutron, as a bound nucleus of two neutrons, can play hidden roles, as it is considered a product resulting from fast neutron-induced nuclear reactions involving the isotopes of lutetium. When being formed in the output channels, a bound dineutron allows for an explanation for unexpected enhancement of reaction cross-sections. We used available data and instrumental spectra to deeply consider the role of the dineutron in order to understand the consequences of its formation and subsequent decay upon transformations of nuclear reaction products. As a result, we obtained experimental confirmation that the half-life of 176gLu is significantly diminished within a certain time interval, which reveals an extremely high estimation for its cross-section of 10E+11 b. This is actually due to 176gLu "burnup", followed by the fusion between 175Lu and a deuteron. This introduces the existence of novel, low-energy reactions and fusion pathways under neutron irradiation, which in-turn, leads to implications for both basic nuclear physics and HEP, along with their applications.

nucl-ex↗

arXiv2025

Endorsing Titanium-Scandium Radionuclide Generator for PET and Positronium Imaging

The development of PET and positronium imaging techniques is strictly related to the availability of suitable radionuclides and robust radiochemistry platforms. Among the emerging candidates, $^{44}$Sc has attracted significant interest due to its favourable physical properties, including a half-life of $\sim$4 hours, a pure $β^{+}$ emission profile, and the additional prompt $γ$-emission that enables advanced triple-photon detection schemes. These characteristics make $^{44}$Sc particularly promising for highresolution imaging and novel quantitative methodologies. However, routine clinical and preclinical implementation requires a practical, sustainable, and cost-efficient production route. In this context, we propose a titanium-scandium radionuclide generator as an optimal solution. This study focuses on optimising the synthesis of the long-lived parent isotope, $^{44}$Ti ($T_{1/2}$ = 59.1 years), from which $^{44}$Sc can be selectively eluted in a chemically pure form when needed. An analysis of various production pathways was conducted, including proton and deuteron reactions on scandium, as well as $α$-particle and lithium-induced reactions on calcium, to determine the most efficient reaction parameters, target design, and expected yield. Furthermore, we identify some existing cyclotron facilities suitable for implementing this technology. Results indicate that efficient $^{44}$Ti production is achievable using proton beams in the 20-30 MeV range under extended irradiation conditions. The proposed generator system would enable routine and decentralised $^{44}$Sc supply. Its integration with the novel J-PET scanner may significantly reduce diagnostic costs and improve access to advanced PET imaging in regions with limited medical imaging infrastructure.

physics.med-ph↗

arXiv2024

Formation of bound dineutrons in the ${}^{175}Lu (n, {}^2n) {}^{174g}Lu$ nuclear reaction and its cross section

The dineutron as a bound chargeless nucleus of two identical nucleons has been attracting attention for many decades. In addition to the study of the formation of a bound dineutron in the outgoing channel of some specific nuclear reactions, cross section estimates have been gaining interest as research target. We used a traditional neutron activation technique to irradiate Lu samples followed by measurements of the induced activity with HPGe spectrometer in order to detect gamma-peaks of the ${}^{175}Lu (n, 2n)^{174g}Lu$ reaction product when this reaction channel is not open for incident neutron energies. Based on two measurements of the instrumental gamma ray spectra of Lu samples we reliably identified the presence of the ${}^{174g}Lu$ isotope in the outgoing channel of the ${}^{175}Lu(n, {}^2n)^{174g}Lu$ nuclear reaction. Also, the cross section for this nuclear reaction was obtained and to be equal $33.5 \pm 5.9$ mb. For the first time, the dineutron as a nuclear reaction product was indirectly detected via statistically significant observation of the induced activity of ${}^{174g}Lu$ with corresponding cross-section estimate.

nucl-ex↗