GOES Flux vs STIX counts

Fig. 1: Scatter plot of STIX counts versus GOES flux in log-log scale and histogram of STIX counts versus GOES flux . STIX counts are divided by the squared distances between Solar Orbiter and the Sun. 1045 flares with look-angles from the Earth smaller than 90 degrees are selected.

File:Goes-stix-flux-fit.png

Fig. 2 A profile of the histogram shown in Fig. 1. A cubic function fit is fitted to the profile.

The GOES flux of a flare is estimated using

flux=10^(p0+p1*x+p2**x^2+p3*x^3),

with x=log10(stix_peak_counts)/r^2

where p0, p1, p2 are the parameters from the polynomial curve fit, peak_counts is the STIX QL LC peak counts and r is the distance between the Sun and solar orbiter in units of au.