Acceleration of the anomalous component of cosmic rays revisited R. Kallenbach1,2, K. Bamert2, and M. Hilchenbach1 1Max Planck Institute for Solar System Research, 37191 Katlenburg-Lindau, Germany 2Physikalisches Institut, University of Bern, 3012 Bern, Switzerland
Received: 24 Apr 2009 – Revised: 24 Jun 2009 – Accepted: 28 Jul 2009 – Published: 13 Oct 2009
Abstract. In the years 2004 and 2007, the instruments onboard the Voyager 1 and 2
spacecraft delivered unprecedented data on the structure of the solar
wind termination shock. This shock has been assumed to be responsible
for the acceleration of the anomalous component of cosmic rays from a
pick-up ion seed population derived from the interstellar neutral gas
penetrating the heliosphere. In expectation of the Voyager observations
near the termination shock and in the heliosheath region, detailed models
have been developed on the acceleration mechanism for the anomalous
cosmic rays and on the structure of the termination shock. Here, an
overview on the models on injection mechanisms into first-order Fermi
acceleration, stochastic acceleration in the supersonic and subsonic
solar wind, shock mediation by suprathermal ions, and on shock reformation
by ions reflected at the shock is given. Comparing the results of these
models to the Voyager observations, we try to synthesize an updated picture
on the acceleration process of the anomalous cosmic rays.
Citation: Kallenbach, R., Bamert, K., and Hilchenbach, M.: Acceleration of the anomalous component of cosmic rays revisited, Astrophys. Space Sci. Trans., 5, 49-60, doi:10.5194/astra-5-49-2009, 2009.