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Name: Sprinkles
Status: student
Grade: 9-12
Location: WI
Country: N/A
Date: 4/18/2005

What would happen if a proton and a neutron collided?

Dear Sprinkles,

All sorts of things could happen depending on the energies involved (how fast the proton and neutron are moving when they collide).

At low energies, they would just scatter off each other "elastically". That means they do not change their structure at all and do not produce any new particles. At very high energies (where I have studied what happens) all sorts of things can and do happen. First you can produce many new particles, transforming the kinetic energies of the nucleons (protons and neutrons are called nucleons) into other particles such as pi mesons, photons, strange particles, and even more exotic particles. You could also tear apart the nucleons, changing them to quite different kinds of particles. The subject is quite complicated, but fascinating.

Best, Dick Plano, Professor of Physics emeritus, Rutgers University


What would happen depends greatly on how fast the proton and neutron are moving:

If moving slowly, nothing much would happen at all. They might bounce off each other. They might just "ignore" each other.

If moving quickly, with a large amount of energy, they are more likely to interact. They might cause each other to slow down and release radiation.

If moving very fast, a huge amount of energy, they will produce many different particles and antiparticles. Much of the energy in their motion will be converted to particles (E=mc^2). There will be electrons, muons, pions, and K-particles flying all over.

Dr. Ken Mellendorf
Physics Instructor
Illinois Central College

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