Fig. 1. Diagram of FILD system layout

Fig. 2. Diagram of scintillator probe

Fig. 3. (a) Change in brightness of the scintillator luminescence image captured using the CCD camera of shot 113 598; (b) Changes in I_p, N_e, IU1, FILD01, NF3, and RA1 in 2~5 s of shot 113 598; (c) Energy count of lost runaway electrons in 2~5 s of shot 113 598

Fig. 4. Model of stainless steel and ZnS(Ag) coating established in Geant4

Fig. 5. Relationship between incident electron energy and number of luminescent photons of the scintillator without a magnetic field under vertical incidence

Fig. 6. Logarithmic coordinate axis of 0~4 MeV

Fig. 7. Energy response curve of the scintillator to electrons

Fig. 8. Simulated luminescence curves of electrons divided into two energy segments, after passing through the stainless steel, multiplied by different weights according to Fig.6

Fig. 9. Relationship between scintillation proportion of secondary particles and incident electron energy

Fig. 10. Effect of thickness of ZnS(Ag) coating on luminescence under vertical incidence

Fig. 11. Variation in number of luminescent photons with incident angle at different incident energies

Fig. 12. Relationship between number of scintillation photons and incident energy at different magnetic field values (color online)

Fig. 13. Relationship between number of scintillation photons and incident energy at different magnetic field angles (color online)

Fig. 14. Relationship between number of scintillation photons and incident energy at different pitch angles (color online)

Fig. 15. Relationship between number of photons and pitch angle for different incident energies (color online)