type II seesaw and RGE implementation

Question how to implement a model or how to change a model implementation
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jaburico
Posts: 4
Joined: 9. May 2020, 05:47

type II seesaw and RGE implementation

Post by jaburico » 10. Jul 2020, 01:33

Hello, I have a little question about implementation of type II seesaw in SARAH. The triplet model with hypercharge is implemented in SARAH without the yukawa triplet term. When I tried to implement only this term in tree level works (the neutrino mass), but in one loop level something was wrong. When I implemented I used this lagrangian

"Yt/Sqrt[2] epsTensor[lef1,lef2] epsTensor[lef2b,lef3] l.trip.l"

after, i defined the mass of neutrino, in the section DEFINITION[EWSB][MatterSector], as

" {{vL},{Fv0,PMNS}}"


In the section DEFINITION[EWSB][DiracSpinors] I defined the neutrino spinor as

"Fv ->{ Fv0, conj[Fv0]}"


In the file parameters.m I defined the mixing matrix and the yukawa triplet matrix as

{Yt,{
Description -> "Yukawa-triplet",
Dependence -> None,
Form -> Symmetric,
DependenceNum -> None,
DependenceOptional -> None,
DependenceSPheno -> None,
Real -> False,
LesHouches -> Yt,
LaTeX -> "Y_{t}",
OutputName -> Yt}},



{PMNS,{
Dependence -> None,
DependenceNum -> None,
DependenceOptional -> None,
DependenceSPheno -> None,
Real -> False,
LesHouches -> UVMIX,
LaTeX -> "U^V",
OutputName -> UV}},


And, in the particles.m file I defined the neutrinos as


{Fv,{
Description -> "Neutrinos",
FeynArtsNr -> 1,
LaTeX -> "\\nu",
Mass -> {LesHouches, LesHouches, LesHouches},
OutputName -> "nu",
PDG -> {12, 14, 16},
ElectricCharge -> 0,
Width -> {External, External, External}}}



These are the only changes that I made in the model, but didnt work the CalcRGE comand, there is an error in the yukawa loop calculation.


After, I tried to do the RGE contraction by hand

ContractionRGE[Yt]=epsTensor[lef1,lef2] epsTensor[lef2b,lef3];
ContractionRGE[Yt[a__]]=ContractionRGE[Yt];

But didn't work...

MDGoodsell
Posts: 17
Joined: 25. Aug 2017, 08:41

Re: type II seesaw and RGE implementation

Post by MDGoodsell » 13. Jul 2020, 11:50

The triplet with hypercharge model is not currently correctly implemented in SARAH (I only recently discovered this) since there is apparently an issue with the ContractionRGE statement, which at the moment should not be used until we are able to correct it.

A future release of SARAH will have a correction to the model (and also the type II seesaw, I have a working implementation), once we have decided the best way to circumvent the problem.

jaburico
Posts: 4
Joined: 9. May 2020, 05:47

Re: type II seesaw and RGE implementation

Post by jaburico » 14. Jul 2020, 05:35

Many thanks for the reply. I will wait for the new implementation!

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