What is the energy equivalent of a proton-antiproton pair?

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SUMMARY

The energy equivalent of a proton-antiproton pair can be calculated using Einstein's equation E=mc². The mass of a proton is 1.67 x 10-27 kg, leading to an energy equivalent of approximately 1.5 x 10-10 joules or 939 MeV. To produce a proton-antiproton pair, the smallest total gamma ray energy required is in the GeV range, specifically through the process of pair production, where high-energy photons can create particle-antiparticle pairs. Understanding the relationship between mass-energy equivalence and gamma rays is crucial for grasping these concepts.

PREREQUISITES
  • Understanding of Einstein's E=mc² equation
  • Knowledge of mass-energy equivalence
  • Familiarity with particle physics concepts, specifically pair production
  • Basic comprehension of energy units, including MeV and GeV
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  • Research the process of pair production in particle physics
  • Learn about the properties and applications of gamma rays
  • Study the conversion between MeV and GeV for energy calculations
  • Explore advanced topics in particle-antiparticle interactions
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Students and educators in physics, particularly those focusing on particle physics and energy-mass relationships, as well as anyone interested in the principles of high-energy physics and gamma ray interactions.

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Homework Statement


The mass of a proton is 1.67 multiplied by 10-27 kg.

(a) Find the energy equivalent of the proton's mass in joules.
(b) Convert this value to eV.
(c) Find the smallest total g ray energy that could result in a proton-antiproton pair.

Homework Equations


Einstein's famous E=mc^2

The Attempt at a Solution


I figured out (a) and (b), but am absolutely clueless as to how to approach (c). What is a "g ray"? Thanks for all your help!

For (a) I got 1.5e-10
For (b) I got 939 MeV
The answer for (c) is in GeV - not really sure what this means either.
 
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A gamma ray? Seems to be the only thing making sense in that context.
 
Hmmm... Okay, thanks. But I'm unclear about what to do with that information.
What if I do E=mc^2 with m being the combined mass of the proton and the antiproton (so really just 2 times the 1.67 etc.) and get that energy, does this get me anywhere? How do I connect that with gamma rays?
 
I don't know which educational level you are so I cannot really judge what's being asked of you. If "g ray" means gamma rays, then the question is either simplistic (to the point of being wrong) or a good deal more complicated than a) and b).

Simplistic version:
Gamma rays, more precisely the photons contained in a gamma ray, at very high energies can "spontaneously" transform into a particle anti-particle pair, usually an electron anti-electron pair (they actually do not do that spontaneously but only in the presence of a reaction partner, but that is exactly the complication I am ignoring here). This process is called pair production http://en.wikipedia.org/wiki/Pair_production" . The same way, a proton anti-proton pair could be produced by a gamma ray (photon). I do think that is the process that your question asks about. I find it a bit advanced to ask for pair production if you never heard about it.

More realistic version: In reality, the reaction partner has to be taken into account. You don't want details about that.

Final remark: Did I understand you correctly that you do not know what "GeV" is? That is giga-electronvolt: 1 GeV = 1000 MeV.
 
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Wow, thanks! That was really thorough and I understand the question now. Thanks for taking your time to help me! I truly appreciate it!
 

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