Used file for the fit: SDD_normalized-Efficiency_point-source_with-air_all-levels.csv

parameters
offset a	slope b
-8.07015e-05	0.0045681

Covariance matrix
3.62987e-11	-1.40647e-09
-1.40647e-09	5.78192e-08

used data points for fitting
energy [keV]	efficiency	efficiency error	nuclide
53.15	9.39319e-05	6.6981e-06	Ba133
80.98	2.38711e-05	1.51814e-06	Ba133
26.34	0.0008386	7.22782e-05	Am241
33.18	0.00041976	4.35769e-05	Am241
59.53	7.77834e-05	6.66722e-06	Am241
