What Is the Minimum Photon Energy Needed to Produce a Proton-Antiproton Pair?

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To produce a proton-antiproton pair, the minimum photon energy required is determined by the rest mass energy of the particles involved. The relevant equation is E^2 = p^2c^2 + m^2c^4, where the rest mass of the proton and antiproton is crucial. Since the photon has zero rest mass, its energy is entirely based on momentum. The total energy needed for the pair production is twice the rest mass energy of a proton, which is approximately 1.88 GeV. Understanding the conservation of momentum and energy is essential in solving this problem.
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Homework Statement



How much photon energy would be required to produce a proton-antiproton pair? Give the answer in SI units.

Homework Equations



E^2=p^2c^2+m^2c^4
E=pc+pc
p=mc
E=2*m*c^2

The Attempt at a Solution



I seem to be confused I know the KE would be zero I also know this would not exist in real life but I need to find the min energy so KE of the photon pairs is 0. I am not sure if the equation has to do with the mass of a photon or the momentum of the photons. In either case I don't know what the mass of a photon would be. I read it was zero but can't figure out how to use this formula then.
 
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ok... mass of a photon is zero... I think we all know that. But its momentum is not... we can agree on that too I think. Now, your key equation is
E^2=p^2 c^2+m^2 c^4[\tex]<br /> where m here is the rest mass of your particle, p is its momentum and E is its total energy. To do your question: remember 4-momentum is conserved...etc
 
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