Transport of Positrons in the Interstellar Medium
نویسنده
چکیده
This work investigates some aspects of the transport of low-energy e (Ek . 1 MeV) in the interstellar medium (ISM). We consider resonance interactions with magnetohydrodynamic (MHD) waves above the resonance threshold. Below the threshold, collisions take over and deflect e in their motion parallel to magnetic-field lines. Using Monte-Carlo simulations, we model the propagation and energy losses of e in the different phases of the ISM until they annihilate. We suggest that e produced in the disk by an old population of stars (SNIa, LMXB), with initial kinetic energies below 1 MeV, and propagating in the spiral magnetic field of the disk, can probably not penetrate the Galactic bulge.
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