• Login
    View Item 
    •   NWU-IR Home
    • Research Output
    • Faculty of Natural and Agricultural Sciences
    • View Item
    •   NWU-IR Home
    • Research Output
    • Faculty of Natural and Agricultural Sciences
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    A local interstellar spectrum for galactic electrons

    Thumbnail
    Date
    2013
    Author
    Potgieter, M.S.
    Nndanganeni, R.R.
    Metadata
    Show full item record
    Abstract
    A heliopause spectrum at 122 AU from the Sun is presented for galactic electrons over an energy range from 1 MeV to 50 GeV that can be considered the lowest possible local interstellar spectrum (LIS). The focus of this work is on the spectral shape of the LIS below 1.0 GeV. The study is done by using a comprehensive numerical model for solar modulation in comparison with Voyager 1 observations at 112 AU from the Sun and PAMELA data at Earth. Below 1.0 GeV, this LIS exhibits a power law with E (1.55 ± 0.05), where E is the kinetic energy of these electrons. However, reproducing the PAMELA electron spectrum averaged for 2009, requires a LIS with a different power law of the form E (3.15 ± 0.05) above 5 GeV. Combining the two power laws with a smooth transition from low to high energies yields a LIS over the full energy range that is relevant and applicable to the modulation of cosmic ray electrons in the heliosphere. The break occurs between 800 MeV and 2 GeV as a characteristic feature of this LIS. The power-law form below 1 GeV produces a challenge to the origin of these low energy galactic electrons. On the other hand, the results of this study can be used as a gauge for astrophysical modeling of the local interstellar spectrum for electrons.
    URI
    http://hdl.handle.net/10394/13651
    https://doi.org/10.1016/j.astropartphys.2013.06.008
    Collections
    • Faculty of Natural and Agricultural Sciences [4818]

    Copyright © North-West University
    Contact Us | Send Feedback
    Theme by 
    Atmire NV
     

     

    Browse

    All of NWU-IR Communities & CollectionsBy Issue DateAuthorsTitlesSubjectsAdvisor/SupervisorThesis TypeThis CollectionBy Issue DateAuthorsTitlesSubjectsAdvisor/SupervisorThesis Type

    My Account

    LoginRegister

    Copyright © North-West University
    Contact Us | Send Feedback
    Theme by 
    Atmire NV