It'll be a bit of an anti-climax, compared to some of that stuff. Those helium atoms are likely to be fuel for our sun somewhere along the line when it's burning down and becoming a white dwarf. Our star isn't big enough to do the supernova thing.
Would scaling up production of Farnsworth fusors help?
When enough "ash" is accumulated (and the star is still big enough) the previous ash begins fusing into some new heavier "ash" rinse and repeat until you get to iron "ash" but no further.
the reason is; every fusion lighter than iron is exothermic
two atoms fuse into something bigger than either, but smaller than both, plus releasing some energy (yay).
when you get to fusing iron you need a ball about 20 miles in diameter and fusing does not give up energy, fusing iron needs to take energy from its environment.
good thing it is not in the middle of a star big enough to grow a twenty mile ball of iron.
and that kids is where supernova come from once iron fusion starts it all goes in moments collapsing the core and the star above where the core was "falls" into that space gravitationally propelled with enough speed that when it hits the opposite side (falling just as fast in the other direction) everything fuses into "whatever"
that is about as exciting as it gets in this universe
The thing that I was interested in is whether or not a helium atom in the Earth‘s atmosphere has a way to be sucked into the fusing layer at some point. It just seems from everything that I’ve learned over the years that there’s a net outflow of that would likely keep the little atom some distance away even if it left Earths gravity well.
I don't know, but think it would be tough for a lone atom.
It seems to me there are three possible fates for that helium, and two of them involve being used up by stellar fusion. The helium atoms get somehow pulled into the sun and so eventually get used up in a fusion reaction, the sun expands during its giant phase and envelops the Earth and the helium eventually gets used up in a fusion reaction, or the helium nuclei gets propelled out of the solar system with the solar wind.
It'd actually be fun to estimate the odds of each option but I honestly have no idea. #3 feels like a long shot.
1. Throw more mass into it, ideally 1+ stars under their own power via Shkavov thruster.
2. Compress it physically with mirrors and particle/photon beams (see inertial confinement fusion)
3. Compress it magnetically with incredulously powerful magnetic fields (see tokamak fusion).
4. Compress it gravitationally by putting a black hole in its center.
5. Make it more explodey by converting half of its mass into antimatter.