W and Z bosons

1. May 19, 2010

What affect does gravity have on W and Z bosons?

2. May 19, 2010

Can electromagnetic force interact with the W and Z bosons given the photon can exchange momentum to mass? The W and Z bosons both have mass so can a force be exchanged?

3. May 19, 2010

bapowell

Since the W and Z bosons each have nonzero energy density, they interact gravitationally. Gravity has the same effect on everything that has stress-energy (anything with energy density and the ability to exert pressure and/or transfer momentum) -- this is a result of the equivalence principle on which general relativity is based.

4. May 19, 2010

bapowell

Only particles with electric charge interact with photons -- mass has nothing to do with it. In the standard model of particle physics, it's possible to have interactions of the form:

(W+) + (W-) ----> photon + Z

but this is not the same as the photon 'interacting' with the Z. There is no direct interaction (for example, there is no coupling term like ZZA, where A = photon) that is allowed in the standard model. This is because the Z is neutral, and A only couples to charged particles.

5. May 19, 2010

If the interaction can involve the W+ and W-.this must affect the interaction W bosons have with other particles. Does the W boson curve in magnetic fields?

6. May 19, 2010

bapowell

Sure. The W bosons are electrically charged particles. As such, they couple directly to the photon (there are AW+W- terms in the standard model). A W boson will trace out a curved path in a magnetic field just as an electron would.

7. May 19, 2010

So would this force exchange still occur in beta decay and would this force then be transferred to particles involved, like the electron neutrino?

8. May 19, 2010

ansgar

Yes .

9. May 19, 2010

Is the W boson the link in electromagnetic interaction? Are fermions influenced by electromagnetic force through W boson interaction? If not how can we differentiate between charged fermions and fermion boson interaction in magnetic fields?

10. May 19, 2010

bapowell

No. Photons are the mediators of the electromagnetic force. The W/Z bosons mediate the weak force. There is no way to distinguish a charged boson from a charged fermion by measuring its path through a magnetic field. The curvature of the path of a charged particle through a magnetic field is useful for determining the particle's mass.

11. May 19, 2010