Comparing simulated and experimental spectral line splitting in visible spectroscopy diagnostics in the HL-2A tokamak

We established the passive-visible spectroscopy diagnostics (P-VSD) and active-VSD (A-VSD) spectral splitting models for the HL-2A tokamak. Spectral splitting due to the influence of electromagnetic fields on the spectra in VSD is studied. Zeeman splitting induced by the magnetic field (B) is used to distinguish reflected light overlap in the divertor for P-VSD. Stark splitting caused by the Lorentz electric field (E_Lorentz) from the neutral beam injection particle's interaction with the magnetic field (V_beam×B) is used to measure the safety factor q profile for A-VSD. We give a comparison and error analysis by fitting the experimental spectra with the simulation results. The distinguishing of edge (scrape-off layer and divertor) hydrogen/deuterium spectral lines and the q profile derived from the spectra provides a reference for HL-2M VSD.