How do neutron stars generate pulsars?

Neutron stars generate pulsars primarily by emitting beams of radiation that sweep across space as the star spins. When a massive star exhausts its nuclear fuel, it undergoes a supernova explosion, leaving behind a dense core that becomes a neutron star. These neutron stars have extremely strong magnetic fields and rapid rotation rates.

As the neutron star rotates, the misalignment of its magnetic axis and rotational axis causes the radiation emitted from the magnetic poles to be projected outward. If this beam is oriented such that it sweeps past Earth, we observe it as regular pulses of radiation, similar to a lighthouse beam sweeping across the landscape. This is what makes neutron stars detectable as pulsars from vast distances, creating a characteristic pulsing signal as they rotate. The precise nature of the rotation and the magnetic field is critical to the formation of pulsars.

The other choices do not accurately describe the mechanism by which pulsars are formed or detected. While a supernova event leads to the creation of a neutron star, it is the combination of its rotation and magnetic field that gives rise to pulsars. The collapsing under gravity is a part of the evolution of the star but does not directly relate to the generation of the pulsar phenomenon.