What Causes a Magnetar’s Magnetic Field?

[SLD]

Magnetars are rapidly spinning neutron stars. They are so dense that the electrons have been jammed into the nucleus and converted the proton into a neutron. Inside there is a swirling mass of neutrons. But they’re neutral. How then do they create a magnetic field?

And while we’re at it, what’s the difference between a pulsar and a Magnetar? Both are rapidly spinning neutron stars, one creates magnetic fields and the other radio waves.

And a third question, how do neutron stars shine? Or do they?

 

[Loren Pechtel]

Magnetars are rapidly spinning neutron stars. They are so dense that the electrons have been jammed into the nucleus and converted the proton into a neutron. Inside there is a swirling mass of neutrons. But they’re neutral. How then do they create a magnetic field?

It's not pure neutrons--there's a constant flux of n -> p + e and p + e -> n, it's just the extreme pressure tips the balance heavily towards the n side.

And while we’re at it, what’s the difference between a pulsar and a Magnetar? Both are rapidly spinning neutron stars, one creates magnetic fields and the other radio waves.

I would figure magnetars are pulsars. We only see a pulsar when one of it's beams sweeps us.

And a third question, how do neutron stars shine? Or do they?

Residual heat. It's going to take them a long time to cool. There are not yet any black dwarfs because there hasn't been time for white dwarfs to cool--and neutron stars have even more mass with even less surface area, they'll cool much slower.