Traps for Antihydrogen

As discussed above our long term goal is antihydrogen spectroscopy with antihydrogen atoms suspended within a neutral particle trap. Hydrogen atoms have subsequently been trapped and used for spectroscopy.*** At ATRAP we are now starting to attempt to trap antihydrogen atoms. (ALPHA is pursing the same goal.)

Ioffe type traps (which make a magnetic field minimum in which an atom can be held by its magnetic moment) destroy the axial symmetry of the Penning traps which hold the positrons and antiprotons until antihydrogen is formed. We were so worried about this that we calculated the trajectories of charged particles within superimposed Penning and Ioffe traps. Our conclusion was that if the particle density was low enough that this problem could be managed, though some reports claimed that this would not be possible. In fact we were able to demonstrate first that antiprotons and positrons remained trapped when we turned on our Ioffe trap. Next, for the first time we produced and detected antihydrogen atoms for the first time when a Ioffe field was present.

No trapped antihydrogen atoms have yet been detected, likely because our antihydrogen atoms are still too energetic to be confined by the relatively week restoring force of the Ioffe trap. Stay tuned.