Study of the effect of strong magnetic fields on the generation of laser-driven electrons in solid targets

The 1 MA Zebra pulsed power generator at UNR produces longitudinal and transverse magnetic fields of 1-3 MG. The effect of strong external magnetic fields on the propagation of fast electron in solid targets was studied using the Zebra machine coupled with a 50 TW laser. Coherent transition radiation (CTR) diagnostics was used to observe the spot of fast electrons on the rear side of the target. We studied CTR on Si and CH targets at a laser intensity of (0.3-0.7)x10¹⁹ W/cm². Laser targets 30-50 um thick were placed in an axial magnetic field of 1-1.2 MG generated in a coil load. The optical beampath relayed images of the target to an intensified CCD camera. Plasma filaments have been observed in experiments with CH targets. The image on Si targets without a magnetic field consisted of a 100 um spot of the reverse current and a 20 um CTR core. The CTR intensity decreased when a 1 MG magnetic field was applied.