Acceleration of interstellar pickup protons at the heliospheric termination shock: Voyager 1/2 energetic proton fluxes in the inner heliosheath

Fluxes of energetic protons in the range from 30 keV up to several MeV measured at the Voyager 1/2 spacecraft downstream of the heliospheric termination shock can be explained by shock-drift acceleration theory, which includes variations of the magnetic field direction in a vicinity of the shock. The variations can be connected with the sector structure of the interplanetary magnetic field near th...