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We present the first simulations evolving resolved spectra of cosmic rays(CRs) from MeV-TeV energies (including electrons, positrons, (anti)protons, andheavier nuclei), in live kinetic-MHD galaxy simulations with star formation andfeedback. We utilize new numerical methods including terms often neglected inhistorical models, comparing Milky Way analogues with phenomenologicalscattering coefficients $\nu$ to Solar-neighborhood (LISM) observations(spectra, B/C, $e^{+}/e^{-}$, $\bar{p}/p$, $^{10}$Be/$^{9}$Be, ionization,$\gamma$-rays). We show it is possible to reproduce observations with simplesingle-power-law injection and scattering coefficients (scaling with rigidity$R$), similar to previous (non-dynamical) calculations. We also find: (1) Thecircum-galactic medium in realistic galaxies necessarily imposes a$\sim10\,$kpc CR scattering halo, influencing the required $\nu(R)$. (2)Increasing the normalization of $\nu(R)$ re-normalizes CR secondary spectra butalso changes primary spectral slopes, owing to source distribution and losseffects. (3) Diffusive/turbulent reacceleration is unimportant and generallysub-dominant to gyroresonant/streaming losses, which are sub-dominant toadiabatic/convective terms dominated by $\sim0.1-1\,$kpc turbulent/fountainmotions. (4) CR spectra vary considerably across galaxies; certain features canarise from local structure rather than transport physics. (5) Systematicvariation in CR ionization rates between LISM and molecular clouds (or Galacticposition) arises naturally without invoking alternative sources. (6) Abundancesof CNO nuclei require most CR acceleration occurs around when reverse shocksform in SNe, not in OB wind bubbles or later Sedov-Taylor stages of SNeremnants.

First Predicted Cosmic Ray Spectra, Primary-to-Secondary Ratios, and Ionization Rates from MHD Galaxy Formation Simulations