(a) 2D histogram showing the bin-wise normalised probability density of proton temperature T_p vs collisional age, τ_pp. The black-filled circles indicate the median T_p values in each τ_pp bin, while the dashed lines represent the 15th and 85th percentiles. The red line shows a power-law fit to the median trend, with the fitted scaling exponent indicated. (b) Similar 2D histogram of the magnetic fluctuation power |δB_rms|² vs τ_pp. The median and percentile statistics as well as the power-law fit are shown.