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

parameters
offset a	slope b
-1.6451e-06	9.43398e-05

Covariance matrix
8.07442e-15	-3.29487e-13
-3.29487e-13	1.3958e-11

used data points for fitting
energy [keV]	efficiency	efficiency error	nuclide
53.15	2.09806e-06	1.0183e-07	Ba133
80.98	4.99199e-07	1.77434e-08	Ba133
26.34	1.59723e-05	1.08443e-06	Am241
33.18	8.58718e-06	7.68032e-07	Am241
59.53	1.52337e-06	1.02488e-07	Am241
