Understanding Neutron Beta Decay: The Role of W Boson and Energies Involved

[chis]

Most accepted theories make sense, but the energies involved in the beta decay of a neutron into a proton confuses me.
How can a down quark change into an up quark by emiting an electron and an anti electron neutrino via a w boson, the figures don't add up!
Using the figures of mass it goes like this:

Neutron 939ish Mev
Down Quark 4.8 Mev

Wboson 80Gev

Electron .511 Mev
Electron Neutrino 2.2 ev

Up Quark 2.4 Mev

Proton 938 Mev

My question is - Where does the Wboson Get so much energy from?

Thanks
Chris

 

[Meir Achuz]

The W boson is virtual, so its effective mass is given by E^2-p^2, where E and p come from conservation of 4-momentum. This is not the W rest mass.

 

[sir-pinski]

The W boson is a fundamental particle that carries the weak nuclear force responsible for beta decay. It is a very massive particle, with a mass of around 80 GeV. This means that it has a lot of energy stored in its mass. When a neutron decays into a proton, a down quark changes into an up quark, emitting an electron and an electron antineutrino. This process requires a change in the quark's flavor, which is only possible through the exchange of a W boson.

The W boson gets its energy from its mass, which is much higher than the masses of the particles involved in this decay. This energy is released in the form of the electron and the antineutrino, which carry away the excess energy from the reaction. This is similar to how a heavy object falling from a height releases energy when it hits the ground.

It is important to note that the figures you have mentioned are not the actual energies involved in the beta decay process. The masses of the particles are measured in units of MeV/c^2, which is a unit of mass, not energy. To calculate the actual energy involved, we need to use the famous equation E=mc^2, where c is the speed of light. This means that the actual energy released in this process is much higher than the masses of the particles involved. Therefore, the W boson does have enough energy to facilitate this decay process.

I hope this explanation helps to clarify your confusion. The study of particle physics can be complex and confusing, but with patience and persistence, we can understand the fundamental processes that govern our universe. Keep asking questions and seeking answers, and you will continue to deepen your understanding of neutron beta decay and other fascinating phenomena in the world of particle physics.