Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The interstellar cosmic-ray electron spectrum from synchrotron radiation
  and direct measurements   Context: The relation between Galactic cosmic-ray electrons, magnetic fields
and synchrotron radiation. Aims: We exploit synchrotron radiation to constrain
the low-energy interstellar electron spectrum, using various radio surveys and
connecting with electron data from Fermi-LAT and other experiments. Methods:
The GALPROP programme for cosmic-ray propagation, gamma-ray and synchrotron
radiation is used. Secondary electrons and positrons are included. Propagation
models based on cosmic-ray and gamma-ray data are tested against synchrotron
data from 22 MHz to 94 GHz. Results: The synchrotron data confirm the need for
a low-energy break in the cosmic-ray electron injection spectrum. The
interstellar spectrum below a few GeV has to be lower than standard models
predict, and this suggests less solar modulation than usually assumed.
Reacceleration models are more difficult to reconcile with the synchrotron
constraints. We show that secondary leptons are important for the
interpretation of synchrotron emission. We also consider a cosmic-ray
propagation origin for the low-energy break. Conclusions: Exploiting the
complementary information on cosmic rays and synchrotron gives unique and
essential constraints on electrons, and has implications for gamma rays. This
connection is especially relevant now in view of the ongoing PLANCK and Fermi
missions.

12
The categories of this paper are: nucl-th
20
The categories of this paper are: acc-phys
27
The categories of this paper are: comp-gas
11
The categories of this paper are: hep-lat
30
The categories of this paper are: q-alg
25
The categories of this paper are: patt-sol
26
The categories of this paper are: bayes-an
10
The categories of this paper are: q-bio
19
The categories of this paper are: eess
29
The categories of this paper are: funct-an
9
The categories of this paper are: nlin
17
The categories of this paper are: q-fin
18
The categories of this paper are: econ
23
The categories of this paper are: solv-int
36
The categories of this paper are: cmp-lg
4
The categories of this paper are: cond-mat