This solution, along with measurements of and , fixes A and s . To calculate the integrated spectrum, we must therefore first determine the parameters in Eq. We first turn to the normalization A . This determines the normalization constant in Eq. One should bear in mind the allowed variation is at least .
Uncertainties are present in both the flux and the escape pathlength.
The parameters for the flux are sensitive to the extrapolation from the observed, solar system intensity to the interstellar intensity. A i converting from energy per nucleon to energy, and where is the abundance of species i in the cosmic rays. We see that the input power scales as , as it should, and the the input power density is fixed by local measurements of the cosmic ray flux and escape pathlength. We can thus analytically estimate . He, which gives in agreement with our rough analytical estimate .