3/3/2019 The Lives and Deaths of Pulsars

"Consider Again that Periodically Rotating Dot. That's a Pulsar. and its slowing down."

We know that Pulsars (Rotating Neutron Stars) are Rotating Periodically on their Rotational Axis while emitting an intense beam of Electromagnetic Radiation along its magnetic Axis. This beam actually Sweeps out a cone like shape in space and if planet Earth (or any sentient beings with decent radar technology) happen to be in the way of this beam, then the Pulsar will be detectable as a repeating signal.

This rapid rotation actually slows down over time.

Pulsar P - Pdot diagram

Lets understand this diagram

The diagram is plotted by horizontal Rotation Period (P) axis against vertical Period Derivative (dp/dt) axis

Period (P): time taken to spin once
Period derivative (Pdot): instantaneous rate of change of P, basically variability of much the Pulsar is slow down.

Pulsars exist on this diagram. Pulsars of Different Ages and type/ Signature populate the diagram and as they age and slow down they move from the top left (small P and high Pdot) into the lower right hand corner (large P, low Pdot) of the mapping.

Young Pulsars spin really fast taking less time to complete a revolution and have a high rate of change of that Period. Old Pulsars spin Slowly and take a long time to alter the total time to make a complete spin.

They're like old men who can't seem to switch it up on the dance floor and move like before. So after a while, they just stifle up, shut off and die. So the trick to staying young is always keep moving.

And there's a line there called a Death Line where the Pulsar is too slow (Large Period) to generate that signature Electromagnetic beam that makes it detectable from Earth and eventually they too will shut off, ending the Pulsars life as a Radio Source, resulting in one less lighthouse in the Cosmos.

The generation of the EM beam is also tied to the strength of magnetic field (B). Low B equals no Beam.

The Pulsar inside the Heart of the Crab Nebula of 1054 is pretty young.

The P -Pdot diagram is sort of like a HR Diagram but for the lives of Pulsars. Detailing their ages until their final fates

But there is a twist, one that involves a bit of Stellar Vampirism.

How Pulsars may be born again Shining and Fast (Really, really Fast)

(That was a Fury Road reference btw)