Controlled variables evolution for 0.1 $ external reactivity step insertion: (a) reactor thermal power; (b) net reactivity variation; (c) fuel inlet temperature; (d) fuel outlet temperature; (e) fuel average temperature; (f) heat transfer rates in the heat exchangers; (g) intermediate salt minimum temperature; (h) intermediate salt maximum temperature; (i) turbine mechanical power; (m) helium turbine inlet temperature.