neutrons - yes but what would happen if I took a scoop of the star and took it away from the star? Whould I just have a big scoop of neutrons? Would the neutrons disintergrate (fly off into the air?) and leave me with nothing? Would the neutrons revert back to their previous elements? or would they just form new elements?
If you got anywhere near it you would be crushed beyond being seen. If you have some magical device to get near it, then I think we would have to understand how the magic device works to know what the scoop of neutrons would do.
–John
Assuming that you could obtain a scoop of a neutron star and remove it from the high pressure environment, the material would rapidly decay into protons and electrons. No disintegration, no elements in the short term, just charged particles.
Would they break apart into protons and electrons? A neutron is reasonably stable. I don’t think they would stick together as a nucleus without protons around. I would expect them to fly away as individual neutrons.
There was an article on the composition of neutron stars in a recent Sky & Telescope (August issue). Unfortunately, this article is not on line.
Neutrons stars are thought to be composed of several layers: iron crust (a few hundred meters), then superfluid neutrons for several kilometers, then a complicated mixture of protons, neutrons and electrons. Deeper still, the high densities may allow the formation of hyperons. Hyperons are baryons that are made up of an up quark, a down quark and a strange quark. Protons and neutrons (which are also baryons) have just up and down quarks.
At the core of a neutron star the strange quarks start to dominate and you get something called quark matter. This is particles made up of more than three quarks, something that’s not possible with only up and down quarks, but becomes possible with strange quarks.
Anyway, that’s just one model. Another one says that the strange matter in the core will convert the rest of the star to strange matter except for the iron crust. The crust will not be converted because it will be insulated from the rest of the star by a powerful electric field. Anyway this is known as a strange star. They don’t really know if strange stars exist.
OK, forget about a scoop. Suppose that two neutron stars collapse into each other and splash stuff around. I’m not sure what would become of the neutronium, but my best guesses are that it would become either hydrogen or iron. One thing that’s certain is that it wouldn’t remain neutronium. Under “normal” (i.e., not the pressures found in a neutron star) conditions, neutrons aren’t stable by themselves, and will decay to a proton, electron, and antineutrino with a half-life of about 15 minutes. That’s extraordinarily long compared to most unstable particles, but still pretty short on astronomical timescales.