1.4 The Physical Mechanisms and Characteristics
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1.4.2.3 High-Energy Radiation
A high-energy radiation is believed to come from hot spot effects. The mechanism
producing the hot spot effects is similar to the solar flare, a sudden flash of increased
Sun’s brightness near its surface. Pulsars are the remnants after the supernova explosions of massive stars. The stars have extremely high temperature as they explode.
With ending the supernova explosions, original neutron stars are produced in their
interior cores. Meanwhile, the temperatures on the surfaces of the neutron stars
without thermonuclear reaction will cool gradually. In the neutron stars evolving
and cooling, there are discrepancies of declining rates of their surface temperatures.
Therefore, it will occur that local temperatures are higher than around ones on the
surfaces of the stars. The higher temperature regions are called the hot spots, and
their particles are very active and have higher speeds. When the high-speed particles
impact the around-low-speed ones, X-ray radiations will be produced. Obviously,
the radiations from the pulsars occur possibly in the hot spots on their surfaces rather
than near the magnetic poles.
1.4.2.4 Accreting Matter Radiation
In the binary system, the accretion disk can be built around the pulsar by absorbing
the matter from the companion star. The matter is accelerated along the magnetic
field lines under a strong magnetic field, and thus gravitational potential energies are
transformed into kinetic ones so that the falling velocities of the matter can get to
10
5 km/s. Along the magnetic field lines, the materials impact continuously at such
high velocity on the solid crusts of neutron stars, and then the releasing energies
will be transformed into the high-energy particle radiations, such as X-rays, near the
magnetic poles.
1.4.2.5 Cyclotron Radiation
Cyclotron radiation is an electromagnetic radiation emitted by accelerating nonrelativistic electrons deflected by a magnetic field. The Lorentz force on the electrons
acts perpendicular to both the magnetic field lines and the electrons’ motions through
them, creating accelerations of the electrons that cause them to emit radiation as a
result of the accelerations they undergo, as they spiral around the lines of the magnetic
field. The polarization of the radiation may be understood from a description of the
electron acceleration as seen by an observer. For the simplest case of the observer in
the plane of gyration, with no streaming motion, the polarization is linear. An observer
above or below the plane will see a circular component, giving elliptical radiation
whose ellipticity diminishes to zero at edge of the beam where the polarization
approaches pure circular. A cross-section across the cone of radiation from an electron
with a large component of velocity along the field line shows similar polarization
characteristics. The cyclotron radiation from plasma in the interstellar medium or
25
1.4.2.3 High-Energy Radiation
A high-energy radiation is believed to come from hot spot effects. The mechanism
producing the hot spot effects is similar to the solar flare, a sudden flash of increased
Sun’s brightness near its surface. Pulsars are the remnants after the supernova explosions of massive stars. The stars have extremely high temperature as they explode.
With ending the supernova explosions, original neutron stars are produced in their
interior cores. Meanwhile, the temperatures on the surfaces of the neutron stars
without thermonuclear reaction will cool gradually. In the neutron stars evolving
and cooling, there are discrepancies of declining rates of their surface temperatures.
Therefore, it will occur that local temperatures are higher than around ones on the
surfaces of the stars. The higher temperature regions are called the hot spots, and
their particles are very active and have higher speeds. When the high-speed particles
impact the around-low-speed ones, X-ray radiations will be produced. Obviously,
the radiations from the pulsars occur possibly in the hot spots on their surfaces rather
than near the magnetic poles.
1.4.2.4 Accreting Matter Radiation
In the binary system, the accretion disk can be built around the pulsar by absorbing
the matter from the companion star. The matter is accelerated along the magnetic
field lines under a strong magnetic field, and thus gravitational potential energies are
transformed into kinetic ones so that the falling velocities of the matter can get to
10
5 km/s. Along the magnetic field lines, the materials impact continuously at such
high velocity on the solid crusts of neutron stars, and then the releasing energies
will be transformed into the high-energy particle radiations, such as X-rays, near the
magnetic poles.
1.4.2.5 Cyclotron Radiation
Cyclotron radiation is an electromagnetic radiation emitted by accelerating nonrelativistic electrons deflected by a magnetic field. The Lorentz force on the electrons
acts perpendicular to both the magnetic field lines and the electrons’ motions through
them, creating accelerations of the electrons that cause them to emit radiation as a
result of the accelerations they undergo, as they spiral around the lines of the magnetic
field. The polarization of the radiation may be understood from a description of the
electron acceleration as seen by an observer. For the simplest case of the observer in
the plane of gyration, with no streaming motion, the polarization is linear. An observer
above or below the plane will see a circular component, giving elliptical radiation
whose ellipticity diminishes to zero at edge of the beam where the polarization
approaches pure circular. A cross-section across the cone of radiation from an electron
with a large component of velocity along the field line shows similar polarization
characteristics. The cyclotron radiation from plasma in the interstellar medium or