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Galactic electron and positron properties from cosmic ray and radio observations

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 نشر من قبل Dario Grasso
 تاريخ النشر 2013
  مجال البحث فيزياء
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We perform a consistent modeling of cosmic ray electrons, positrons and of the radio emission of the Galaxy. For the time we reproduce all relevant data sets between 1 GeV and 1 TeV including the recent AMS-02 positron fraction results. We show that below few GeV cosmic ray and radio data require that electron primary spectrum to be drastically suppressed and the propagated spectrum be dominated by secondary particles. Above 10 GeV an electron + positron extra-component with a hard spectrum is required. The positron spectrum measured below few GeV is consistently reproduced only within low reacceleration models. We also constrain the scale-height of the cosmic-ray distribution showing that a thin halo ($z_t lsim 2 kpc$) is excluded.

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