Plasma effective charge diagnostics at the Globus-M2 tokamak

The conventional method for determining the effective ion charge Zeff is based on measurements of the bremsstrahlung intensity in the spectral regions free from line radiation. This paper describes the design of the Zeff diagnostics at the Globus-M tokamak as well as the results of the first measurements. With allowance for the emission intensity estimates, the geometry of the experiment was chosen; the filter monochromators for recording bremsstrahlung were designed and manufactured. Using the Thomson scattering data on T e (R) and n e (R) profiles, time dependences Zeff (t) were obtained in several shots of the Globus-M tokamak. The results of simulations Z eff performed using the ASTRA transport code are consistent with these measurements.