On the Influence of Vacuum Conditions on The Power Level of Electromagnetic Waves Generated by A Relativistic Magnetron

doi:10.26565/2312-4334-2025-1-42

A.B. Batrakov National Science Center «Kharkiv Institute of Physics and Technology», Kharkiv, Ukraine https://orcid.org/0000-0001-6158-2129
S.I. Fedotov National Science Center «Kharkiv Institute of Physics and Technology», Kharkiv, Ukraine https://orcid.org/0000-0002-7216-0615
O.М. Lebedenko National Science Center «Kharkiv Institute of Physics and Technology», Kharkiv, Ukraine https://orcid.org/0009-0004-2243-8393
I.N. Onishchenko National Science Center «Kharkiv Institute of Physics and Technology», Kharkiv, Ukraine https://orcid.org/0000-0002-8025-5825
O.L. Rak National Science Center «Kharkiv Institute of Physics and Technology», Kharkiv, Ukraine https://orcid.org/0009-0000-6683-1235
M.V. Volovenko National Science Center «Kharkiv Institute of Physics and Technology», Kharkiv, Ukraine https://orcid.org/0000-0001-7216-2058
Yu.N. Volkov National Science Center «Kharkiv Institute of Physics and Technology», Kharkiv, Ukraine https://orcid.org/0009-0002-0557-8090

DOI: https://doi.org/10.26565/2312-4334-2025-1-42

Keywords: Relativistic magnetron, Microwave radiation, Vacuum system, Adsorption pump

Abstract

The high-power microwave radiation, generated in a relativistic high-voltage pulsed magnetron with the range of 8 mm, was experimentally investigated. The factors that negatively affect the generation of microwave radiation were experimentally studied and analyzed. It was determined that the low pressure in the vacuum diode of the magnetron also was associated with the processes reducing the efficiency and duration of the pulse generation. The air components are known to be the major residual gases in the magnetron vacuum diode. During the magnetron operation, a significant increase in the pressure of the residual atmosphere of hydrocarbons, water vapor, and hydrogen is to be observed. A vacuum system was composed to pump them out, thus ensuring the magnetron optimal operation. A cryogenic condensation-adsorption pump was developed and applied for the new vacuum system allowing to increase the evacuation rate of the main residual gases. The peculiarity of the developed pump is that the pumping element with the adsorbent has a double working surface due to the use of a corrugated form of the sorption cartridge. Another feature of the pump is its efficiency, which is achieved due to the use of nitrogen vapors for cooling the space between the walls. Due to the use of the cryogenic means of pumping, it became possible to obtain the pressure at the level of 1·10^-6 Torr, thus achieving an increase in the microwave radiation of the relativistic magnetron by 25 percent.

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