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arXiv · 1308.1591

A Heliopause Spectrum for Electrons

M. S. Potgieter·R. R. Nndanganeni·E. E. Vos·M. Boezio
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Abstract

We present a heliopause spectrum for galactic electrons over an energy range from 1 MeV to 50 GeV at 122 AU from the Sun. This spectrum can be considered the lowest possible local interstellar spectrum (LIS). This is obtained by using a comprehensive numerical model for solar modulation in comparison with Voyager 1 observations during 2010 and PAMELA data at Earth. Below about 1 GeV, this LIS exhibits a power law with E^(-(1.5 plus minus 0.1), where E is the kinetic energy of these electrons. Reproducing the PAMELA electron spectrum for 2009 requires a LIS with a different power law above about 5 GeV of the form E^(-3.15 plus minus 0.05). The heliopause spectrum thus consists of two power laws with a break between about 800 MeV and about 2 GeV.

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M. S. Potgieter, R. R. Nndanganeni, E. E. Vos, M. Boezio. 2013-08-07. A Heliopause Spectrum for Electrons. https://arxiv.org/abs/1308.1591

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