# Would an antimatter beam create multiple matter-antimatter explosions?

To expand upon the question - in an atmosphere, would a beam of pure antimatter (disregarding technical difficulties creating such a beam or passing it through a medium) interact with the matter in the atmosphere to annihilate each other and release energy in the form of a blast?

Just had a thought that if the counterparts of antimatter and matter - say hydrogen and anti-hydrogen or proton-antiproton met in such a way, would it create such an outcome?

Obviously, if its a beam, then the density of particles in the beam matters a lot for the annihilation rate and so does the density and composition of the atmosphere.

## 1 Answer

Here is an image of an antiproton beam going through a bubble chamber:

It is a representative picture of what happens when an antiproton meets a proton : annihilation into many particles which further interact with the bubble chamber matter electromagnetically and will finally decay into neutrinos, muons, which will escape the chamber due to weak interactions and subsequently decay to electrons and another two neutrinos each. The electromagnetic energy will be deposited in matter, the energy carried by the neutrinos will disappear to space as they do not interact. Maybe 50% of the 2GeV energy will be deposited in matter.

Observe that there is no chain reaction possible, and that the energy deposited will depend on the number of antiprotons on the beam as the number of protons is of the order of $10^{23}$ per mole. The liquid in this case would boil (as the bubbles are boiling liquid) and pictures would not be possible. Similar dissipation would happen impinging on any matter. Explosions in the sense of macroscopic explosions no.