Generation of high-power electromagnetic radiation by a beam-driven plasma antenna

• Published in: Plasma physics and controlled fusion Vol. 58; no. 4; pp. 45009 - 45015
• Main Authors: Annenkov, V V, Volchok, E P, Timofeev, I V
• Format: Journal Article
• Language: English
• Published: IOP Publishing 01.04.2016
• Subjects: beam-plasma interaction; Beams (radiation); Controlled fusion; Electromagnetic radiation; Electromagnetic waves; Mathematical models; Plasma (physics); plasma antenna; Plasma antennas; Three dimensional
• ISSN: 0741-3335; 1361-6587
• DOI: 10.1088/0741-3335/58/4/045009

In this paper we study how efficiently electromagnetic radiation can be generated by a relativistic electron beam with a gigawatt power level during its injection into a thin magnetized plasma. It is shown that, if the transverse beam and plasma size is compared with the radiation wavelength and the plasma density is modulated along the magnetic field, such a beam-plasma system can radiate electromagnetic waves via the antenna mechanism. We propose a theoretical model describing generation of electromagnetic waves by this plasma antenna and calculate its main radiation characteristics. In the two-dimensional case theoretical predictions on the radiation efficiency are shown to be confirmed by the results of particle-in-cell simulations, and the three-dimensional variant of this theory is used to estimate the peak power of sub-terahertz radiation that can be achieved in beam-plasma experiments in mirror traps.