How is a Higgs boson created?

I have read a lot on Higgs bosons, yet I do not fully comprehend how they are created and how they are "flicked off" the Higgs field. I have also had trouble comprehending why a Higgs boson quickly becomes unstable and decays into more common particles.

How is a Higgs boson created and how and why does it quickly decay?

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– Kyle Kanos Dec 13 '13 at 15:41

A higgs boson is created at an accelerator just like any other particle, by converting energy to mass, according to the famous equation

$$E = mc^2$$

If you take the LHC as example, then protons are accelerated to nearly light speed, having enough energy to create particles as heavy as the higgs.

For a particle to decay it needs phase-space (i.e. the particles that the parent particle decays to need to be lighter than the parent particle) and no conserved quantities that would forbid a decay (e.g. charge conservation).

Since the higgs is heavy and has no quantum number that would forbid a decay, it has a very short lifetime.

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The higgs can, however, decay to intermediate, off-shell heavier particles, e.g. WW or ZZ, with appreciable branching ratios. The ZZ to 4 leptons is an important decay channel. – innisfree Dec 13 '13 at 16:27
They are off the mass shell, i.e. they are not heavier. – pfnuesel Dec 13 '13 at 16:33
Yes of course, maybe my comment was trivial! – innisfree Dec 13 '13 at 19:12