A Re-Evaluation of Cosmic Ray Populations with Recent Observations

Recent direct measurements of cosmic ray elemental spectra have revealed new spectral structures that challenge conventional models of cosmic ray acceleration and propagation. This includes spectral hardening at ~200 GV and possible softening at ~10 TeV. Previously, a model with 4 acceleration populations was used to fit the cosmic ray spectra. Each population is represented by a power law with a rigidity dependent exponential cutoff. This model is used to fit the primary elements, including H, He, C, O, Ne, Mg, Si, and Fe between 30 - 10^8 GeV. The primary elements are grouped by their observed rigidity dependencies to speed up the fitting procedure without sacrificing the fit’s consistency. The fitting procedure returns spectral indices for each population of each element. This updated analysis incorporates recent direct measurements from CALET, DAMPE, and ISS-CREAM, as well as recent indirect measurements from LHAASO. The new spectral indices from this analysis are compared with previous results. Changes in each element's contribution to the all particle spectrum and the average particle mass, , are also compared.