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Mixing with Effective Operator

Posted: 20. May 2016, 10:55
by RRuffault
Hi Florian,

I'm trying to implement a dimension-5 effective operator which induces a mixing after EWSB in a Non-Susy model with SARAH 4.8.6. Taking the SM as basis, I just add the content:

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FermionFields[[6]] = {Trip, 1, {{T0L/Sqrt[2],TpL},{TmL,-T0L/Sqrt[2]}}, 0, 3, 1, -1};
FermionFields[[7]] = {Sing, 1, sL, 0, 1, 1, -1};
The relevant Lagrangian for my problem is:

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LagHC  = ...  - 1/2 Mtrip Trip.Trip - 1/2 Msing Sing.Sing + keff Sing.Trip.conj[H].H;
After EWSB, there is a mixing due to the last term of the above Lagrangian. I take it into account by adding in the model file:

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DEFINITION[EWSB][MatterSector]= {..., {T0L,sL},{OO,NN}} };
When I run SARAH, I have the following result:

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In[3]:= MassMatrix[OO]
Out[3]= {{Mtrip, 0}, {0, Msing}}
It seems that the dimension-5 mixing term is not considered. Is there a way to fix this or am I doing something wrong?

Let me know if I can be of any further help.

Best,
Ronan

Re: Mixing with Effective Operator

Posted: 20. May 2016, 11:13
by FStaub
Hi,

this is not a bug. The simple reason is that SARAH doesn't support effective operators, see for instance: http://stauby.de/sarah_wiki/index.php?t ... ric_models

SARAH focuses on renormalisable operators because this is assumed in all calculations done by SARAH which go beyond tree-level (RGEs, loop masses, ...).

Best,
Florian

Re: Mixing with Effective Operator

Posted: 20. May 2016, 16:59
by RRuffault
FStaub wrote: this is not a bug. The simple reason is that SARAH doesn't support effective operators, see for instance: http://stauby.de/sarah_wiki/index.php?t ... ric_models
Thank you for your quick answer! I have to admit that I didn't see this information in the manual.