Spectra of the persistent preburst radiation for Case I involving the IC process with T_age = 10² yr corresponding to L_w ≃ 5.0 × 10³⁶ erg s⁻¹ (the dashed line) and T_age = 0 yr corresponding to L_w ≃ 9.6 × 10⁴⁴ erg s⁻¹ (the solid line). We set P_orb = 10 day, corresponding to a ≈ 3.9 × 10¹¹ cm and M_c = 1 M_⊙. The blue lines show the preburst radiation spectrum of Case I. The green line indicates the IC spectrum. The corresponding parameters we used are p = 2.2, γ_m = 10⁴, and γ_M = 10⁶.