To the vacuum conditions that provided the process of electromagnetic waves generated by a relativistic magnetron

TL;DR

This study investigates how vacuum conditions affect electromagnetic wave generation in a relativistic magnetron, demonstrating that improved vacuum via a cryogenic pump enhances EHF radiation efficiency.

Contribution

A novel cryogenic condensation-adsorption pump was developed to improve vacuum quality, increasing EHF radiation output in a relativistic magnetron by 25%.

Findings

Vacuum pressure reduction improves magnetron performance.

Cryogenic pumping increased EHF radiation by 25%.

Residual gases like hydrocarbons and water vapor impact efficiency.

Abstract

The powerful EHF radiation generated in a relativistic high-voltage pulsed magnetron of the 8 mm range is experimentally investigated. The factors that negatively affect the generation of EHF radiation are experimentally investigated and analyzed. It is determined that the processes that reduce the efficiency and duration of the generation pulse also include low pressure in the vacuum diode of the magnetron. It is known that the main residual gases in the vacuum diode of a magnetron are air components. During magnetron operation, there is a significant increase in the pressure of the residual atmosphere: hydrocarbons, water vapor, and hydrogen. A vacuum system was designed to evacuate these gases to ensure optimal operation of the magnetron. For the new vacuum system, a cryogenic condensation-adsorption pump was developed and applied, which allowed to increase the rate of pumping out the main residual gases. The peculiarity of the developed pump is that the pumping element with the adsorbent has a working surface that is twice as large as the one in the corrugated form of the sorption cartridge. Another feature of the pump is its efficiency, which is achieved through the use of nitrogen vapor for cooling the inter-wall gap. The use of cryogenic pumping means made it possible to obtain a pressure of 1E-6 Torr, which led to a 25 percent increase in the EHF radiation of the relativistic magnetron.