Numerical divergences in Box Diagrams for FlavorKit

Questions about the interface between SARAH and SPheno as well as the FlavorKit functionality
Post Reply
ldarme
Posts: 4
Joined: 1. Dec 2016, 16:51

Numerical divergences in Box Diagrams for FlavorKit

Post by ldarme » 9. Jan 2017, 15:21

Dear Florian,

When using FlavorKit to calculate low energy observables, numerical divergences are reported in the Message.out file from SPheno. They concern D00check, D0C0check and B0. They seem to be related to box loops involving the pseudo-scalar eigenstates. I can see them appearing in different models, including the basic CMSSM model file (I am using the SPheno from the latest SARAH you updated following my last email). Is this something known to you ?

Thanks a lot in advance,
Cheers,
Luc

FStaub
Site Admin
Posts: 822
Joined: 13. Apr 2016, 14:05

Re: Numerical divergences in Box Diagrams for FlavorKit

Post by FStaub » 13. Jan 2017, 10:50

Hi Luc,

yes, these routines throw often errors. This usually appears when massless states are in the loop. However, since these diagrams can't contribute to flavour observables, they are at the end multiplied by zero. I should change at some point the procedure in a way that the loops are only calculated if the corresponding coupling doesn't vanish.

Cheers,
Florian

Post Reply