Portrait of a Dead Star as a Cosmic Disco Ball (Pulsar Wind Nebula)

Massive stars implode as Core-collapse supernovae. Now, what happens to the core? It can either end up as a neutron star or a black hole. Let's take the neutron star scenario here.

The Star Died, But Left Its Angry, Spinning Ghost

The core implodes, sending shock waves to the ambient medium. This forward shock compresses and heats the ambient gas, and propagates sweeping up the material. Now, as the deceleration of the shock drives back a reverse shock into the cold ejecta, heating the metal-rich gas to X-ray-emitting temperatures. But, what's there at the centre? A rapidly-spinning, highly magnetic neutron star. This neutron star, a pulsar, generates an energetic wind of particles and magnetic field. Thus, we have a nebula driven by the winds of a pulsar hosted inside a supernova remnant (SNR) - a pulsar wind nebula (PWN).

Is a PWN an SNR?

No, a pulsar wind nebula and a supernova remnant are not the same. Yes, a pulsar wind nebula is formed after a supernova explosion and the pulsar is a result of the supernova. But, pulsar wind nebulae are created entirely by a confined magnetic wind produced by an energetic pulsar. And, supernova remnants are structures produced by the expanding supernova ejecta and its interaction with the ambient media.

Who Who? Pulsar who?

Pulsars are rapidly-rotating, highly-magnetic neutron stars. They rotate really fast and as time goes forward, they gradually slow down. As this pulsar rotates, it creates a charge-filled magnetosphere. Particles will be accelerated here as they bounce between charge-gaps.

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