Radio data and synchrotron emission in consistent cosmic ray models

Abstract

It is well established that phenomenological two-zone diffusion models of the\ngalactic halo can very well reproduce cosmic-ray nuclear data and the observed\nantiproton flux. Here, we consider lepton propagation in such models and\ncompute the expected galactic population of electrons, as well as the diffuse\nsynchrotron emission that results from their interaction with galactic magnetic\nfields. We find models in agreement not only with cosmic ray data but also with\nradio surveys at essentially all frequencies. Requiring such a globally\nconsistent description strongly disfavors very large ($L\\gtrsim 15$ kpc) and,\neven stronger, small ($L\\lesssim 1$ kpc) effective diffusive halo sizes. This\nhas profound implications for, e.g., indirect dark matter searches.\n