Title:
"Spectral Features of Cosmic-ray Electrons/Positrons from Astrophysical Sources"
Abstract:
We investigate the GeV-TeV spectrum of cosmic-ray electrons and
positrons from astrophysical sources, especially pulsars, and the
injections from continuous and/or multiple electron/positron sources.
First, we find that a continuous injection from a single source
produces a broad peak and a high energy tail above the peak in the
observed electron spectrum, which can constrain the source duration.
As for the case of multiple sources, we find that the average
electron/positron spectrum predicted from nearby pulsars are
consistent with PAMELA, Fermi and H.E.S.S. data. However, the
ATIC/PPB-BETS peak around 500GeV is hard to produce by the sum of
multiple pulsar contributions and requires a single (or a few)
energetic pulsar(s). We also expect a large dispersion in the TeV
spectrum due to the small number of sources, that may cause the high
energy cutoff inferred by H.E.S.S. and potentially provide a
smoking-gun for the astrophysical origin. These spectral diagnostics
can be refined in the near future by the CALET/AMS-02 experiments to
discriminate different astrophysical and dark matter origins. The
spectral signature of the electron/positron escape from the supernova
remnant surrounding a pulsar is also discussed.