When a particle decays and spits off some alpha radiation why doesnt it take with it some of the electrons from its parent particle? I would expect the electrons to "stick" to the helium nucleus and travel with it.

I am guessing it is a matter of moment. The alpha particle flys off at such speed the resting moment of the electrons may make it so they cant follow it... but considering that electrons arent at "rest" and that they have very very little mass I question myself on this answer.

#Physics #NuclearPhysics #Radioactivity #Radiation

@freemo At a quick guess, you're close, but it's energy, not moment. The nuclear decay processes are very short range and all the electrons know about it is via electromagnetism (since they don't participate in the strong interaction, the weak interaction is too short-range, and the electron's mass is too small for gravity to be important). If you want the electrons to leave their orbitals, you need to pump some energy into them. The less-negative electromagnetic potential energy from the reduced nuclear charge isn't necessarily enough for that to happen quickly - the atom just exists as a -2 ion for long enough that the alpha particle has time to escape.

I'm not a particle physicist; just trying piece together what I remember from undergrad physics.

@khird

That adds up with all the speculation and info... It just escapes way too fast for the electron to have a chance to follow it.. though apparently it does happen rarely and when it does produces X-rays.. which adds up.

@freemo @khird The X rays come from inner electrons being occasionally blasted out of the atom by the escaping alpha. (The X rays are emitted as replacement electrons drop into the vacancies.) The kinetic energy of the alpha is far too great for an electron (or two) to hitch a ride.

@lewriley

By the way cant seem to follow you.. says you moved but its to a domain that is blocked for child porn (dont worry not accusing you of that).

@khird

@freemo @khird That's surprising to me. Might be a moderation decision by quoto.org as opposed to a broadly-distributed block list. I just moved from firefish.social back to mas.to and pretty much all of my followers made the jump.