Diagnostic Lithium Beam System for COMPASS Tokamak

The COMPASS tokamak has been re-installed in IPP Prague after its transport from Culham in UK. A Diagnostic Lithium Beam system is being developed for COMPASS tokamak. Its main goal is to provide edge density (Beam Emission Spectroscopy) and edge plasma current (Atomic Beam Probe) measurements to address the scientific programme focused on H-mode and pedestal physics. It features several newly designed and developed parts, including improved emitter and neutralizer. Atomic Beam Probe is an innovatory diagnostic for measurement of poloidal magnetic field and plasma current fluctuations in the plasma edge. Currently, the system is connected to tokamak (August 2011) and first experiments with plasma were performed. The system still undergoes vacuum, neutralization and high voltage testing. This article reviews the concept and current state of the Lithium Beam diagnostic for COMPASS and provides its first test results