Bubble chamber picture of annihilation of antiproton with proton

The dark lines in this picture are produced by charged particles as they force their way through liquid deuterium.

The highlighted track is an antiproton , produced in the decay of
an antilambda into an antiproton and a .

In the top left corner of the picture, this antiproton annihilates with a proton constituent of a deuteron, producing a 6-pronged annihilation 'star’. (If it had struck a neutron , the number of prongs would, by charge conservation, have to be odd.)

This event was important in particle physics because it was the first observation of the anti-particle of the omega minus .For details of this event, click here.

For another example of antiproton click on the picture below.