sarah recchia (Gran Sasso Science Institute)
The transport of cosmic rays (CRs) in the Galaxy is known to be affected by the presence of winds launched from the Galactic disc. When these winds are pre-assigned, it is easy to check that the effects on transport are limited to energies below $\sim 10$ GeV. Moreover a boundary condition needs to be imposed at large distances (above and below the disc) to ensure the stationarity of the problem. However, a Galactic wind can be driven by the gradient in the CR pressure, and the hydrodynamics of such winds has been studied in the past. We discuss a semi-analytical kinetic calculation of CR transport in a CR driven wind, that allows one to determine the CR spectrum and spatial distribution in the Galaxy, as well as the characteristics of the wind itself. In this highly non-linear approach, diffusion is due to scattering on self-generated Alfven waves and both diffusion coefficients and slope of the B/C ratio are outputs of the problem. Moreover, no artificial boundary condition at spatial infinity is needed. We discuss the implications of this physical model for the following observables: 1) CR spatial distribution in the disc of the Galaxy; 2) CR anisotropy; 3) Spatial profile of the diffuse radiation due to CR interactions. We also discuss preliminary results of the case in which neutral hydrogen in the circum-disc region is transported by the wind due to charge exchange reactions.
|Collaboration||-- not specified --|
|Registration number following "ICRC2015-I/"||656|