Antimatter (Proton & Anti-Proton Annihilation)

[OlivasCA]

In Antimatter production in a labratory, does anyone know the principle element used to generate antimatter such as anti-protons?

 

[Nyme]

Antimatter production usually involves two elements: the other being protons (i.e. hydrogen nuclei), which are accelerated to relativistic velocities, and the other being a heavier element with high Z (proton number).

It doesn't really matter which specific element the target is made of, just as long as it is a heavy element. I would suggest something on the order of lead or gold.

Edit: that for antiprotons. Positrons are easier to make: they are emitted in beta plus decay, and also it is possible to accelerate electrons to large velocities, let them hit a target and produce high-energy bremsstrahlung radiation. The radiation (1 MeV photons or higher energy) hits nuclei, producing electron-positron pairs.

 

[Bob S]

At Fermilab, they accelerate large currents of protons to about 120 GeV, and slam them into a copper target. Tungsten was used for a while but could not take the instantaneous shock stresses, and cracked. Gold might be good, but 50 pounds or more would be expensive. Gold would get extremely radioactive, and require remote handling. They get lots of stuff out of the copper. Most is positively charged. The negatively charged particles include electrons, muons, pions, kaons, and antiprotons. They select about 9 GeV/c momenta particles and store them.

 

[Vanadium 50]

I don't believe it's copper. I believe it's an alloy called Inconel.