Extended Data Fig. 3: MCMC-derived probability distributions of the fit parameters for pixel P3.

This pixel is located in ROI 3 at x = 959.0″ and y = − 162″ and marked by the small blue plus sign in Fig. 1. The upper right panel shows the microwave spectrum from this pixel by the open circles (mean values) and the error bars at ± 1σ level. Blue curves display a set of trial theoretical spectra employed within MCMC fitting. The free parameters of the fitting included (from top to bottom): the magnetic field B, the thermal number density n_th, the nonthermal number density n_nth, the spectral index δ, the viewing angle θ, and the minimum energy \({E}_{\min }\) in the power-law electron spectrum. Individual panels display solid black horizontal/vertical lines that indicate the best-fit values from the GSFIT minimization reported in¹⁰. The median values of the MCMC probability distributions are shown with the dotted blue horizontal/vertical lines. Dashed black lines in the histograms along the diagonal indicate ± 1-σ standard deviation of a given parameter. Correlations between all possible pairs of parameters are shown as two-dimensional histograms of the probability distributions in off-diagonal panels. The contour levels represent 39.3%, 60%, and 80% of the maximum. The outer contour level represents approximately the 1-σ region of a 2D Gaussian distribution (1 − e^−0.5).