# Large-scale antimatter production

From what I can find, presently the only known means of producing antimatter consist of directing particle accelerators at various targets, and only infrequently getting positrons or anti-protons as byproducts of particle interactions.

Assuming a sufficiently large source of energy: Have more efficient means of producing antimatter been conceived?

And based on these is there a known upper bound on antimatter production efficiency? For example:

1. If all known theory requires that an anti-particle be produced with its particle pair, then efficiency will always be under 50%.
2. Are there known processes for "transmuting" matter into anti-matter? If so, do these allow for a theoretical upper-bound on production greater than 50% of input energy?
• Note that you get vast numbers of positrons (and every other light anti-particle) out of energetic hadron interactions. It's just that cooling them into beams is difficult and inefficient. Jul 14, 2016 at 22:00
• @dmckee - So, ignoring the "engineering" problem, can hadron colliders produce a nearly 50% ratio of antimatter that is theoretically harvestable (i.e., before the antimatter annihilates/decays in a time or distance so small that it is theoretically inseparable)? Or is the "harvestable" ratio of anti-matter to input-energy known for such interactions? Jul 14, 2016 at 22:03
• Pair production makes particles and anti-particles in equal numbers, though in some cases they are the same thing (i.e. $\pi^0$s), but most decay too fast to do anything with them. The positrons can be captured and cooled into beams as can $\mu^+$s. Charged anti-pions can be partially focused and used to make neutrino beams., as can charged anti-kaons to a lesser extent. Collecting anti-protons in order to make neutral anti-hydrogen is hard but has been done. Jul 15, 2016 at 0:34
• There is no known mechanism that would allow matter to antimatter conversion. You can only produce particle antiparticle pairs. Aug 17, 2021 at 12:26
• There are some experiments with very powerful lasers to produce large quantities of matter/antimatter pairs. Aug 18, 2021 at 12:19