OBSERVATIONS OF PULSARS

Neutron stars have very intense magnetic fields, about 1,000,000,000,000 times stronger than Earth's own field. However, the axis of the magnetic field is not aligned with the neutron star's rotation axis. The combination of this strong magnetic field and the rapid rotation of the neutron star produces extremely powerful electric fields, with electric potential in excess of 1,000,000,000,000 volts. Electrons are accelerated to high velocities by these strong electric fields. These high-energy electrons produce radiation (light) in two general ways:

  1. Acting as a coherent plasma, the electrons work together to produce radio emission by a process whose details remain poorly understood;
  2. Acting individually, the electrons interact with photons or the magnetic field to produce high-energy emission such as optical, X-ray and gamma-ray.

WHAT MAKES IT PULSE?

Simply put, pulsars are rotating neutron stars. And pulsars pulse because they rotate! Pulsars pulse because the rotation of the neutron star causes the radiation generated within the magnetic field to sweep in and out of our line of sight with a regular period.

A Diagram of pulsar, showing its rotation axis and its magnetic axis

Pulsars have jets of particles moving almost at the speed of light streaming out above their magnetic poles. These jets produce very powerful beams of light. We see pulsars turn on and off as the beam sweeps over the Earth. Neutron stars for which we see such pulses are called "pulsars", indicating that the source of energy is the rotation of the neutron star.

Crab Pulsar "On"

Crab Pulsar "Off"

Thanks For Your Visit