Letter to the Editor

Energetic particles from the outer heliosphere appearing as a secondary pick-up ion component

¹ Institute for Problems in Mechanics of the Russian Academy of Sciences, Prospect Vernadskogo 101-1, 119526 Moscow, Russia
² Institut für Astrophysik und Extraterrestrische Forschung der Universität Bonn, Auf dem Hügel 71, 53121 Bonn, Germany e-mail: hfahr@astro.uni-bonn.de

Corresponding author: S. V. Chalov, chalov@ipmnet.ru

Received: 17 December 2002
Accepted: 19 February 2003

Abstract

In measured pick-up ion spectra a special spectral feature has been identified on the high side of the pick-up ion injection energy which cannot be explained as due to energy diffusion of primary pick-up protons originating from ionized interstellar H-atoms. As we can show, however, in the following article, this feature can be explained as a secondary pick-up ion feature due to ions originating from the charge exchange ionization of energetic neutral H-atoms entering the inner heliosphere and coming from their birth places in the heliosheath. It may thus be the case that energetic neutral H-atoms from the heliosheath region, searched for by experimenters for quite some time now, have already been seen as secondary pick-up ions in special features of measured distribution functions.