What is the minimum energy photon that can produce a positron electron pair?

What is the minimum energy photon that can produce a positron electron pair?

1.02 MeV
Because an electron has a rest mass equivalent to 0.511 MeV of energy, a minimum gamma-energy of 1.02 MeV is required for this pair production. Any excess energy of the pair-producing gamma-ray is given to the electron–positron pair as kinetic energy.

What happens when a proton collides with an electron?

When a proton and an electron collide, it’s called an electron capture. Electron capture is one of two processes in which a neutron is produced. The other process is a beta decay.

What happens when protons and neutrons collide?

In order to form atomic nuclei, the nucleons (the scientific word for protons and neutrons) must be able to collide and stick together. In the early universe the key reaction was the collision of a proton and a neutron to form a deuterium nucleus (an isotope of hydrogen).

How much energy is released when a positron and electron annihilate each other?

The total amount of energy released when a positron and an electron annihilate is 1.022 MeV, corresponding to the combined rest mass energies of the positron and electron. The energy is released in the form of photons. The number of photons depends on exactly how the positron and electron annihilate.

What is the minimum photon energy needed to create a proton antiproton pair?

The process of creating a particle-antiparticle pair is called pair production. To produce this pair, you need a boson with sufficient energy. The Mass-Energy of both a proton and an anti-proton is about 938 Mev/c2.

What is the minimum ray energy needed to produce a positron?

So, the minimum energy required to produce an electron positron pair is twice the rest mass energy of the electron and is equal to 1.02 MeV. If the photon has an energy greater than 1.02 MeV, it would get converted into the kinetic energy of the electron and positron.

How do protons collide?

In most proton collisions the quarks and gluons inside the two protons interact to form a wide array of low-energy, ordinary particles. Occasionally, heavier particles are produced, or energetic particles paired with their anti-particles. Very occasionally, these collisions produce new particles for us to find.

What is the minimum amount of energy released in the annihilation of an electron-positron pair?

The rest mass of an electron or positron is m0=9.1×10-31kg. In the annhilation of an electron positron pair, the rest mass of the two particles is converted into energy. ∴ Minimum energy released, E=2m0c2=2(9.1×10-31)(3×108)2joule.