Broadband spectral energy distributions (SEDs) for the SNR HESS J1731−347 (top) and SN 1006 (bottom). A purely leptonic (blue solid) and a hadronic (red solid) scenario are shown in the test particle case (s_e,p = 2.0). The red dashed line shows the steepest hadronic spectral slope compatible with the data, respectively s_p = 1.5 and 1.7 for HESS J1731−347 and SN 1006. The H.E.S.S. data points for the top and bottom panels are extracted from Abramowski et al. (2011) and Acero et al. (2010), respectively, and the Fermi-LAT 95% confidence level upper limits are derived assuming a spectral index of 2.0.