Flux-resolved spectral parameters derived from the pulse-to-pulse analysis in the 3–70 keV energy range. Different colors represent different observation years, and distinct marker styles indicate observation IDs; time-averaged results for the short-exposure observations (30002007002, 90602328002, 90602328004, and 90602328006) are also shown. The dashed line in the second panel is the theoretical prediction for E_* = 28.097 ± 0.052 keV (see Equation (4)).