Proton/Antiproton

[Jacques]

It is well known that the electron positron anhilation reaction give two photons. I was wondering what was the result of the proton/antiproton anhilation ? Since the proton and the antiproton are made of 3 quark each doesn't the proton/antiproton should give 6 photons (2 for each quark/antiquark) ???

Thanks for your answers.

[[Tycho?]]

Good question, not one I could answer though. It would definately be more energy than the electron/positron reaction, but I dont know if it would make more photons, higher energy photons, or both.

[5614]

The result can be 2 photons... however it could also be an electron + positron, they'd then probably annihilate to form photons anyway, but you could seperate them.

 

There could be other possibilities I'm not 100% sure on all my annihilation processes.

[Daecon]

You could probably work out the math when you match up what the 6 quarks are, and what you can make out of them.

[m4rc]

Electrons and positrons do not always produce two photons when they annihilate. Sometimes they produce 3 photons. The number of photons will depend on the total spin of the electron/positron pair. They will produce 2 photons if their total angular momentum is 0, and 3 photons if the total angular momentum is 1.

 

I know less about proton/antiproton decay but a quick search revealed that "when antiprotons annihilate with protons, the annihilation process does NOT produce gammarays immediately. Instead, the products of the annihilation are from three to seven particles called pions." (from http://www.transorbital.net/Library/D001_S01.html) . I believe that these pions then decay, each emitting 2 photons.

 

Therefore the result of antiproton decay is several photons.

[swansont]

I know less about proton/antiproton decay but a quick search revealed that "when antiprotons annihilate with protons' date=' the annihilation process does NOT produce gammarays immediately. Instead, the products of the annihilation are from three to seven particles called pions." (from http://www.transorbital.net/Library/D001_S01.html) . I believe that these pions then decay, each emitting 2 photons.

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Neutral pions decay into two photons, but charged pions decay into a muon and a mu neutrino (one of the two being an antiparticle). (list of mesons) The muon then decays into an electron and two neutrinos.

 

If the protons and antiprotons have kinetic energy when they collide, you can get heavier particles out of the reaction.

[Jacques]

Thanks for your answers and for the links!

These anilation processes are more complex than I thaught.