The first antiprotons were caught last night in the new ALPHA 2 catching trap, the first component of the next generation of the ALPHA experiment to be installed. This is the representation of the first 'hot dump' -- where we release the captured antiprotons, allowing them to annihilate on the surrounding apparatus. The annihilation converts the antiprotons into high-energy charged particles, which are counted by detectors surrounding the apparatus. Because we detect the annihilations at the same time as we release the trap, we can be sure that the antiprotons have been captured in the trap.
Read more about the Penning trap in How ALPHA works.
The catching trap, designed in collaboration with staff at the Daresbury Laboratory and the Cockcroft Institute in the UK, will be responsible for cooling 5MeV antiprotons from the AD, and supplying them on demand to the ALPHA 2 atom trap, which will be installed later this year. Construction has been taking place at the AD for the last month, and even though there's a long way to go before the apparatus achieves its full potential, this is a big milestone for us at ALPHA.