noun
particle beam
Technical term in physics for a stream of charged or neutral particles, such as in accelerators or cosmic rays.
加速器で粒子線を発生させる。
A particle beam is generated in the accelerator.
粒子線治療はがんの新しい治療法の一つだ。
Particle beam therapy is one of the new cancer treatments.
ビーム (beam) is a general loanword used in many contexts (light, laser, etc.), while 粒子線 is strictly a physics term for particle beams.
Compound of 粒子 (りゅうし, 'particle') and 線 (せん, 'line, beam'). A straightforward modern technical term.