Best-fit spectral energy distributions for Cygnus X-1. The top panel corresponds to Model A and the bottom panel to Model B. Radio data is taken from Fender et al. (2000), IR fluxes from Persi et al. (1980) and Mirabel et al. (1996), soft X-ray observations below 5 × 10¹⁸ Hz (by BeppoSAX) from Di Salvo et al. (2001), hard X-ray data above 20 keV (by INTEGRAL) from Zdziarski et al. (2012), soft gamma-ray data (by COMPTEL) from McConnell et al. (2002), the Fermi-LAT measurements and upper limits from Malyshev et al. (2013), and the MAGIC upper limits from Albert et al. (2007). Down-pointing arrows indicate upper limits. The data are not simultaneous.