Link between CP violation and supersymmetry?

[epsilon]

I have been looking in SUSY and have seen that the CP violation of B mesons into two muons is one of the key facts that has cast further doubt over SUSY. I don t really understand how the CP violation of B mesons is a sign of SUSY issues, so if you are able to clear this up for me that would be much appreciated.

 

[mfb]

I think you mean the decay of B_s mesons to two muons. This has nothing to do with CP violation. The standard model prediction for the branching fraction is tiny, but new fields/particles could have enhanced that significantly as they could add new decay mechanisms.

 

[epsilon]

Yes that's what I mean, forgot to include the subscript. Could you explain what you mean by the branching fraction?

 

[mfb]

The probability that the particle decays to two muons. On average, about 3 out of a billion B_s decay to two muons.

For B_d, the probability is even lower with 1 out of 10 billions.

 

[ChrisVer]

As for susy issues, I'd say that the main concern about the branching ratios come from the fact that SuSy will allow additional channels for a process...
So let's say that for the SM you have X% predicted events...
and for SM+SUSY you have X+Y % predicted events...
If experiment allows for X% but not for X+Y% then SUSY [models] gets disfavored. Of course you have a lot of parameters to play with in such scenarios, like playing with the masses of the spartners and so on... But the more you play with it, SuSy can change a lot..