Proportion of the total CR energy measured in the solar neighborhood attributed to the CS source as a function of time and for each energy bin. As current estimates of the energy required to form the FBs span between 10⁵⁶ and 10⁵⁷ erg, this quantity is left as a free parameter, the obtained range of values being represented by the colored surfaces. For each of them, the dotted (dashed) line represents the scenario in which 10⁵⁶ erg (10⁵⁷ erg) is required to form the FBs. The estimated age of the FBs (1–6 Myr) (Guo & Mathews 2012; Zhang & Guo 2020) is represented by the orange surface.