Prediction of pair production via WIMP decay? (Layman question)

[feathermoon]

Hello,

This may sound silly, don't be afraid to let me know just how silly though!

I've read that predictions are made using the standard model. I do not know the details of this process. I understand pair production occurs randomly in a vacuum, but I wondered if there was an underlying reason aside from a vacuum potential.

Anyway, would there be a way to calculate characteristics/distribution of WIMPs (if they exist) assuming they decay in some way? I know WIMPs aren't supposed to interact electromagnetically, but could they still weakly?

 

[Bill_K]

feathermoon, WIMPs are hypothetical, as are many of their properties. Typically they are assumed to interact with each other via gravitation and the weak force. The belief is that two WIMPs can annihilate to produce a neutrino-antineutrino pair, which is one way of detecting their presence.

 

[kurros]

Anyway, would there be a way to calculate characteristics/distribution of WIMPs (if they exist) assuming they decay in some way? I know WIMPs aren't supposed to interact electromagnetically, but could they still weakly?

Well, if they decay it has to be extremely slowly, otherwise they would all be gone by now. Generally they are assumed to be stable. As Bill_K says they are also generally assumed to be their own anti-particle (at least they are in a number of popular models), so they can collide with each other and annihilate into things. Neutrinos are just one possibility though, they can usually annihilate into all sorts of things. High energy photons and electron-positron pairs are common final states, and there are numerous experiments currently looking for dark matter indirectly by looking for otherwise unexplainable excesses of gamma rays and/or positrons coming from somewhere, typically the galactic centre
(where the dark matter halo should be densest).

 

[sambristol]

Never be afraid nor ashamed to think 'silly' as silly is good (Paul Dirac predicted the existence of antimatter by considering the the silly solution to his equation which is the basis of quantum electro dynamics (QED) – Carl Anderson found the the anti electron the same year) – OK Dirac did get some of the basics wrong he hoped it was the proton.

You ask about WIMPS

The clue is in the name. WI – weakly interacting MP – massive particles

If they exist then they will be beyond the standard model

The problem is. If they interchange via the weak force why do we not see them in experiments

Or do they decay in other way and if they have so much mass why don't t see it

Hope this helps



Sam