Do W bosons exist as massive particles or are they just energy equivalence effects?

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OmCheeto
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About 40 years ago, someone told me that free neutrons decay with a half life of around 14 minutes.
About 10 years ago, I discovered that W bosons were involved, and that they are about 100 times as massive as a proton.

Do W bosons really exist as "massive" particles for their very brief lifespan?
Or is their mass merely derived from the energy equivalence equation, and no one really knows?

Thanks!
 
I don't think your two statements are in conflict. We determine the masses of many things - most unstable particles - through relativistic kinematics ("energy equivalence equation" is just a special case), But yes, the W has a rest mass.
 
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OmCheeto said:
About 10 years ago, I discovered that W bosons were involved, and that they are about 100 times as massive as a proton.
The "W bosons" in neutron decays are not real particles. They do not need to have the mass of real W bosons.
 
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Also, it's good to know that most weak decays don't have enough energy to create a real (on shell) and massive W bosons, so only virtual (off shell) W bosons are created in the process.
But the top quark is massive enough to create a real W boson in the decay process, which makes its decay a lot faster than other particles.
 
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mfb said:
The "W bosons" in neutron decays are not real particles. They do not need to have the mass of real W bosons.

Garlic said:
Also, it's good to know that most weak decays don't have enough energy to create a real (on shell) and massive W bosons, so only virtual (off shell) W bosons are created in the process.
But the top quark is massive enough to create a real W boson in the decay process, which makes its decay a lot faster than other particles.

I think this is what I was really asking; "Is the W- Boson involved in free neutron decay real, or virtual?"
And your's was the answer I was hoping for.
It's sometimes difficult for laymen to determine from pop-sci articles when particles are real, and when they're virtual.

Double thanks!
 
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OmCheeto said:
Double thanks!

Double no problem
 
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