Predicted flux above 1 TeV using Eq. (1) as a function of the distance to the source. Mass-loss rates are given in units of M_⊙ yr⁻¹ assuming u_w = 10 km s⁻¹ and the parameters described in Sect. 3.1, for t = 20 days (solid lines) and t = 150 days (dashed lines) after the SN explosion. The Mass-loss rate is given for each pair of lines of the same color. The expected flux for SN 1993J is computed using Eq. (1) and t = 20 days. The CTA sensitivity for a 50 h long observation is taken from Acharya et al. (2013). The ten ULs on the flux above 1 TeV derived in this study are also shown (see text).