2013ApJ...777..114B -
Astrophys. J., 777, 114 (2013/November-2)
Electron-positron flows around magnetars.
BELOBORODOV A.M.
Abstract (from CDS):
The twisted magnetospheres of magnetars must sustain a persistent flow of electron-positron plasma. The flow dynamics is controlled by the radiation field around the hot neutron star. The problem of plasma motion in the self-consistent radiation field is solved using the method of virtual beams. The plasma and radiation exchange momentum via resonant scattering and self-organize into the "radiatively locked" outflow with a well-defined, decreasing Lorentz factor. There is an extended zone around the magnetar where the plasma flow is ultra-relativistic; its Lorentz factor is self-regulated so that it can marginally scatter thermal photons. The flow becomes slow and opaque in an outer equatorial zone, where the decelerated plasma accumulates and annihilates; this region serves as a reflector for the thermal photons emitted by the neutron star. The e ± flow carries electric current, which is sustained by a moderate induced electric field. The electric field maintains a separation between the electron and positron velocities, against the will of the radiation field. The two-stream instability is then inevitable, and the induced turbulence can generate low-frequency emission. In particular, radio emission may escape around the magnetic dipole axis of the star. Most of the flow energy is converted to hard X-ray emission, which is examined in an accompanying paper.
Abstract Copyright:
∼
Journal keyword(s):
plasmas - stars: magnetic field - stars: neutron
Simbad objects:
2
Full paper
View the references in ADS
To bookmark this query, right click on this link: simbad:2013ApJ...777..114B and select 'bookmark this link' or equivalent in the popup menu