Gamma-ray (IC) and X-ray (synchrotron) spectra (spectral energy distribution – SED) produced in the nebula around the Black Widow binary system containing the millisecond pulsar B1957+20 for different model parameters. The spectra are produced by relativistic electrons which scatter the MBR and the infrared photons from the galactic disk. The maximum energies of the electrons are given by Eq. (4) and the minimum energies are equal to E_w = 3 TeV. a) Dependence of SED on the magnetization parameter σ = 0.1 (dashed), 0.01 (dotted), and 0.001 (solid) for the pulsar wind shock radius R_sh = 10¹⁶ cm, the power law spectrum of the electrons with spectral index α = 2.5 and the minimum magnetic field strength B_min = 0.5   μG. b) Dependence of SED on the radius of the pulsar wind shock R_sh = 10¹⁵ cm (dotted), 10¹⁶ cm (solid), and 10¹⁷ cm (dashed), for σ = 0.01, α = 2.5, and B_min = 0.5   μG. c) Dependence of SED on the spectral index of the electrons α = 2.1 (dashed), 2.5 (solid), and 3 (dotted) for R_sh = 10¹⁶ cm, σ = 0.01 and B_min = 0.5   μG. d) Dependence of SED on the minimum value of the magnetic field B_min = 0.5   μG (dotted), 1   μG (solid), and 2   μG (dashed) for R_sh = 10¹⁶ cm, σ = 0.01, and α = 2.5. It is assumed that the relativistic electrons take 10% of the rotational energy lost by the pulsar. The 100 h differential sensitivity of the MAGIC stereo system (thin dotted, Aleksic et al. 2012) and the 100 h CTA sensitivity (Actis et al. 2011) are also marked.