... effect[*]
Appendix A is only available in electronic form at http://www.aanda.org
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... spectrum[*]
As follows from observations of the X-ray flux from the Galactic disk (see Lebrun et al. 2004), similar processes may accelerate particles up to $\la$100 keV in the interstellar medium, although one cannot exclude the possibility that electrons are accelerated to far higher energies.
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Copyright ESO 2006