Possible evolutions of isolated neutron stars

Abstract

Neutron stars are end products of stellar evolution, like black holes and white dwarfs. Since they radiate in all bands of the electromagnetic spectrum and as their densities and magnetic fields are much higher than normal stars, they are essential objects for astrophysics and in general for physics. They have the highest magnetic fields known in the Universe. Evolution of different types of neutron stars is still an open question. In this work, we try to clarify the differences in the evolutions of different types of isolated neutron stars. We suggest three possible isolated pulsar evolution on the rotation period (P) versus temporal change in the P (P_ ) diagram. The P- _P diagram for isolated radio and/or X-ray pulsars, anomalous X-ray pulsars, soft gamma repeaters, dim isolated thermal neutron stars and dim radio quiet neutron stars is constructed. The possible evolutionary tracks for isolated neutron stars are examined. Besides, possible existence of low-mass neutron stars is discussed.