Pulsars
So, as the pulsar rotates around, it sweeps the sky with radiation created
along its magnetic pole. The radiation comes out in a fairly narrow cone.
When ever this cone sweeps past, we see this in the radio:
The pulsar does not itself, "pulse".. rather, the radiation we detect
appears to come in single bursts, or pulses, as the magnetic field sweeps
by our line of sight.
Other Facts about Pulsars:
- Typically do not have visible counterparts (exception: Crab Pulsar!)
- Are frequently found at the centers of Supernova Remnants.
- Pulsars will slowly spin down (they are losing energy putting out
all those pulses of radio light!). As they spin down, their magnetic
fields become more weak, making their radio emission (or pulse) weak.
At some point, their emission become too weak to be detected.
All Pulsars are Neutron Stars.
All Neutron Stars are NOT Pulsars. Why??