Optical Radiation from the Sputtered Species under Excitation of Ternary Mixtures of Noble Gases by the 6Li(n,α)3H Nuclear Reaction Products

Abstract

The present paper examines the luminescence of ternary Ar-Kr-Xe and Ne-Ar-Kr mixtures of noble gases in the spectral range from 300 to 970 nm, excited by the 6Li(n,α)3H nuclear reaction products in the core of a nuclear reactor. A thin layer of lithium applied on the walls of the experimental device, stabilized in the matrix of the capillary-porous structure, serves as a source of gas excitation. During in-pile tests, conducted at the IVG.1M research reactor, thermal neutrons interact via the 6Li(n,α)3H reaction, and the emergent alpha particles with a kinetic energy of 2.05 MeV and tritium ions with a kinetic energy of 2.73 MeV excite gaseous medium. The study was carried out in a wide temperature range. The temperature dependence of the intensity of the emission of the atoms of noble gases and alkali metals, heteronuclear ionic molecules of noble gases were studied. The obtained values of the activation energy of the emission process 1.58 eV for lithium and 0.72 eV for potassium agree well with the known values of evaporation energy. Excitation of alkali metals atoms occurs consequently of the Penning process of alkali metals atoms on noble gas atoms in the 1s-states and further ion-molecular reactions.

Experimental Facility to Study the Threshold Characteristics of Laser Action at the p-s-Transition of Noble Gas Atom upon Excitation by 6Li(n,α)3H Nuclear Reaction Products

“…The second method involves the use of volume sources of charged particles, when a gaseous isotope or its compound, such as 3 He, 235 UF 6 , and 10 BF 3 , are part of the working mixture. Along with the above-mentioned reactions used to ionization and excitation of gaseous medium, another reaction is used-the reaction of interaction of lithium-6 nuclei with thermal neutrons 6 Li(n,α) 3 H. The relatively large mean free path of tritium nuclei in lithium (130 µm) and gaseous media (35 cm in atmospheric pressure of helium) allows for exciting large volumes of gases and providing a large value of power input nested in the gas compared to the reaction products with 10 B.…”

“…Excitation of gaseous media in experiments to study the optical radiation of nuclear-excited plasma conducted at nuclear reactors is realized, as a rule, by nuclear reactions products with thermal neutrons: 3 He(n,p) 3 H, 10 B(n,α) 7 Li, 235 U(n,f)F [1,2,5]. Moreover, the isotopes ( 235 U, 3 He, or 10…”

Results of Experiments under the Physical Start-Up Program of the IVG.1M Reactor

“…In 1990, the reactor underwent modifications that involved replacing the gas-cooled technological channels with water-cooled ones, resulting in the reorientation of the reactor towards a wider range of applications. Reactor irradiation experiments, such as the study of the radiation resistance of optical fibers [6] and the investigation of the spectral-luminescent characteristics of gases [7][8][9], research Energies 2023, 16, 6263 2 of 12 on the interaction between the structural materials of the international thermonuclear experimental reactor (ITER) and hydrogen in reactor irradiation conditions, etc., have become possible.…”

Influence of the Carbidized Tungsten Surface on the Processes of Interaction with Helium Plasma

“…However, such nanostructures are very fragile and easily detach from the surface under high thermal loads, representing a source of tungsten dust, which is a serious threat to lowering the plasma temperature in Tokamaks [ 19 , 20 , 21 ].…”