2D Octupole Magnetic Field Lines from Neutron Star and Its Associated Radiation Pressure

Abstract

In this paper I have found the magnetic field strength of a neutron star, by using flux conservation, which the size of the sun as a progenitor star and its magnitude is Bη=9 × 1014 G which is approximately quadruple of magnetic field of the sun. The dying star collapses to form a neutron star, magnetic flux conservation results in the formation of regions of extremely strong magnetic field near the neutron star. This shows a neutron star is strongly magnetized at birth. This kind of neutron star is called a pulsar and it is supposed radiator. The rotation period of a neutron star is calculated using angular momentum conservation and the result led that, the rotation period of neutron star is τηs ∼ 0.1 s. The sun rotates once every 107 seconds; this implies that a typical neutron star with radius 10 km rotates 108 times faster than the size of our sun with radius 105 km. So a typical neutron star is a pulsar. I have derived the field lines corresponding to a magnetic octupole moment. 2D case-section of the field lines of a neutron star is drawn. The magnetic field of a neutron star is derived from flux conservation and is high during the age of its birth. The octupole magnetic field of a neutron star is maximum at the surface and ceases to zero in the far distant zone, but visible as pair lobes looks like dipole. Finally, the octupole field strength is dominated at the surface than the dipole field, this leads to Neutron stars octupole field near the center is more significant. The radiation from such a source is calculated and is shown to be diffuse. The radiation pressure generated from octupole field lines of neutron star is calculated and the pressure dominates at the surface and rapidly drops it in the far zone. This result leads to violate the known electromagnetic radiation in the far zone is not vanish rapidly. So, this is the neutron star’s unique property, with evidence supported by two rotating axis than other stars with one rotating axis.