Hi,

...was just pondering the endlife of a neutron star.... presuming they rapidly rotate, and that they will absorb ISM and emit radiation, what happens in the long term with these stars? Do they evaporate or grow due to ISM dust collection?

I also wondered whether or not the absorption of a photon onto a neutron would/could change it into a proton, and if so, what energy photon would do that?

You'd think I'd have better things to think about, n'est pas?

From what I've read, neutron stars in the long run slow down more and more until they can no longer accelerate enough charged particles (electrons I think?) to radiate a detectable amount of energy, then ultimately, keep slowing until they are just a ball of neutrons floating through space, with, I presume, little to no angular momentum.

 

http://spiff.rit.edu/classes/phys230/lectures/ns/ns.html

 

As for the photon/proton question, personally, I don't see how a photon (no charge) absorbed by a neutron (neutral charge), could result in a positively charged particle. But then again, my understanding of particle physics isn't great at the moment.

How about this.

 

What happens when too many neutron stars crash into each other and merge with eachother. What will happen if their total mass is far greater than that of a Black Hole

Given enough mass, they themselves will become a blackhole.

 

The center will crush inwards until even neutrons can't resist the crushing force of gravity.

You can't turn a neutron into a proton by hitting it with a photon.

 

You can do it by hitting it with an positron though. The positron could emit a virtual W-boson (and turn into a neutrino) which is absorbed by a down-quark in the nuetron turning it into an up-quark. Since the neutron is udd and the proton is uud, this turns the neutron into a proton.

You can't turn a neutron into a proton by hitting it with a photon.

 

You can do it by hitting it with an positron though. The positron could emit a virtual W-boson (and turn into a neutrino) which is absorbed by a down-quark in the nuetron turning it into an up-quark. Since the neutron is udd and the proton is uud' date=' this turns the neutron into a proton.[/quote']

 

Thanks! that's a great answer - I suspected that it would not be possible use a photon to convert a neutron into a proton, but I just wanted confirmation.

Blimey, there's some bright sparks on this forum!!!

Good stuff!

You can't turn a neutron into a proton by hitting it with a photon.

 

You can do it by hitting it with an positron though. The positron could emit a virtual W-boson (and turn into a neutrino) which is absorbed by a down-quark in the nuetron turning it into an up-quark. Since the neutron is udd and the proton is uud' date=' this turns the neutron into a proton.[/quote']

 

yeah, that's what I meant...