A major milestone has been achieved in the commissioning of the ELI-GBS Linac, with the successful generation of the first electron beam from the RF electron source during July-August 2026. The beam spot as recorded on August 26th by a downstream screen monitor is shown below. The spot has a diameter of approximately 1.75 mm, while the bunch charge, measured by a commercial current transformer, was estimated to be around 80 nC.
The first electrons were generated from the photocathode and successfully accelerated, demonstrating the basic functionality of the electron source and confirming the successful integration of several critical accelerator subsystems. The achievement of first electrons represents the culmination of extensive preparation and commissioning activities at ELI-NP, including installation and alignment of the RF gun, establishment of the required vacuum conditions, commissioning of the High Power and Low-level RF systems, integration of the photocathode laser system, RF-laser synchronization, and verification of the beam diagnostics and control system.
The Gamma System Department staff gratefully acknowledge the support provided by the enthusiastic team of operators from the Canadian Light Source, who guided and assisted with the initial search for the electron beam during the second half of July 2026.
