Astrophysics and Space Sciences Transactions www.astrophys-space-sci-trans.net 1810-6528 1810-6536 5 1 2009 10.5194/astra-5-21-2009 http://www.astrophys-space-sci-trans.net/5/21/2009/ http://www.astrophys-space-sci-trans.net/5/21/2009/astra-5-21-2009.html http://www.astrophys-space-sci-trans.net/5/21/2009/astra-5-21-2009.pdf 21 30 2009-08-06 Spectral intensities of Anomalous Cosmic Rays derived from the injection rate at the solar wind termination shock H.-J. Fahr D. Verscharen Argelander-Institut für Astronomie, Universität Bonn, Auf dem Hügel 71, 53121 Bonn, Germany Max-Planck-Institut für Sonnensystemforschung, Max-Planck-Straße 2, 37191 Katlenburg-Lindau, Germany We investigate the well accepted idea that anomalous cosmic ray (ACR) ions originate from suprathermal halo ions by means of diffusive shock acceleration. Usually the seed ions are taken to be the interplanetary pick-up ions, but here we want to enlarge this idea by taking in addition as seed candidates also into account normal solar wind ions which according to our recent calculations are reflected from the termination shock into the upstream solar wind flow and then are also picked-up as suprathermal ions. We start out from an ideally planar shock approximation and fix the ACR spectrum by absolute spectral intensities and maximum ACR energies, taking a precalculated fraction of the suprathermal ion flow as ACR injection rate. Comparison of our calculated spectral intensities with ACR measurements near 94 AU, shows that satisfying data fits only can be achieved, if about three percent of the suprathermal ions swept into the shock structure enter into the Fermi-1 acceleration process. 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