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WINDS
B-FIELDS AND MAGNETOTAILS OF HIGH VELOCITY PULSARS
Authors: Romanova
M.M., Chulsky G.A.,
and Lovelace R. V. E.,
We investigate the emission of rotating magnetized
neutron stars due to the acceleration and radiation of
particles in the relativistic wind and in the
magnetotail of the star. We consider that the charged
particles are accelerated by driven collisionless
reconnection. Outside the light cylinder, the star's
rotation acts to wind up the magnetic field to form a
predominantly azimuthal, slowly decreasing with distance, magnetic
field of opposite polarity on either side of the equatorial
plane normal to the star's rotation axis. The magnetic
field annihilates across the equatorial plane, with the
magnetic energy going to accelerate the charged
particles to relativistic energies. For a typical supersonically
moving pulsar, the star's wind extends outward to the
standoff distance with the interstellar medium. At
larger distances, the power output of the pulsar's wind
Ew of the electromagnetic field and relativistic
particles is redirected and collimated into the magnetotail of
the star. In the magnetotail it is proposed that
equipartition is reached between the magnetic energy and
the relativistic particle energy. For such conditions,
synchrotron radiation from the magnetotails may be a
significant fraction of Ew for
high-velocity pulsars. An equation is derived for the
radius of the magnetotail rm(z') as
a function of distance z' from the star. For
large distances z', on the order of the distance
traveled by the star, we argue that the magnetotail has
a "trumpet" shape because of the slowing down of
the magnetotail flow. We compare results with the Guitar
Nebula and Mouse Nebula and conclude that the tail of
the Mouse Nebula may be connected with the long
magnetotail behind the pulsar. We argue that the shock
waves and elongated structures may also be observed in
misdirected or shutoff pulsars and may be used as a
tool for finding these objects.
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