Deriving the cosmic ray spectrum from gamma-ray observationsстатья
Статья опубликована в высокорейтинговом журнале
Информация о цитировании статьи получена из
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Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 18 июля 2013 г.
Аннотация:A fundamental problem of cosmic ray (CR) physics is the determination of the average properties
of Galactic CRs outside the Solar system. Starting from COS-B data in the 1980’s, gamma-ray
observations of molecular clouds in the Gould Belt above the Galactic plane have been used to
deduce the Galactic CR energy spectrum. We reconsider this problem in view of the improved
precision of observational data which in turn require a more precise treatment of photon production
in proton-proton scatterings. We show that the spectral shape dN/dp ∝ p−2.85 of CR protons as
determined by the PAMELA collaboration in the energy range 80 GeV < pc < 230 GeV is consistent
with the photon spectra from molecular clouds observed with Fermi-LAT down to photon energies
E ∼ 1–2 GeV. Adding a break of the CR flux at 3 GeV, caused by a corresponding change of the
diffusion coefficient, improves further the agreement in the energy range 0.2–3 GeV.