Also we can define a mesonic
antiatom as an ordinary antiatomic nucleons with one or more of its antielectrons replaced by positively-charged mesons.
The easiest way to prove that they have made their
antiatom is to annihilate it.
Scientists in Europe recently created the first human-made
antiatom, an atom with all the usual electrical charges reversed.
Also we can define a mesonic
antiatom as an ordinary antiatomic nucleous with one or more of its antielectrons replaced by positively-charged mesons.
Each antimatter atom has antielectrons (positrons), antiprotons, and antineutrons, except the
antiatom of ordinary hydrogen which has no antineutron.
Electrically neutral and no longer deflected by the accelerator's magnetic fields, this
antiatom would move in a straight line before plowing into a silicon target.
Such states are analogous to the gravitational quasi-stationary states of
antiatoms above material surface, predicted in 18, 19].
The Nature paper reports 38 such trapped
antiatoms, which were held for more than a sixth of a second before they escaped and annihilated themselves against the matter in the sides of the container.
These types of selectors may have a wide range of applications and can be built not only for neutron beams, but also for other experiments with UCNs, ultracold atoms, and
antiatoms [16-19], in particular within the GBAR project with ultracold antihydrogen at CERN [20], as well as, probably, with positronium [21] and so forth.
2010 The ALPHA experiment produces antihydrogen that lasts a fraction of a second, opening the door for experiments on the physics of
antiatoms.