This is a memo for SARAH.

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Install 
1. Download SARAH-x.x.x.tar.gz, and untar.
2. Go to your application folder, find Mathematica, and right click it.
3. Choose "Show Package Contents".
4. Move files you get in 1. to Addons/Applications/
5. Boot Mathematica. If you have already booted it, quit it and reboot.

Preparation 
<< "SARAH-4.2.2/SARAH.m"

Commands 
ShowModels
Start["SM"]
SARAS`FirstSteps
CalcRGEs[]
...

RGE
To calculate the beta functions of the SM, do 
    Start["SM"]
CalcRGEs[]
Then the beta functions are stored in files which are generated in /Addons/Applications/SARAH-4.2.2/Output/SM/RGEs/ .
You can see the result by typing some commands. For example, 
    BetaYijk
returns the beta functions of Yukawa. The result is stored in matrix notation, like, 
    { 
 { Yu, 1-loop, 2-loop}
,{ Yd, 1-loop, 2-loop}
,{ Ye, 1-loop, 2-loop}
}.
So you can pick up, for example, top-Yukawa 2-loop beta function by 
    BetaYijk[[1,3]].
According to arXiv:1309.7233, you can see other beta functions by appropriate commands. 
     Gij: Anomalous dimensions of all fermions and scalars 
 BetaGauge: Beta functions of all gauge couplings 
 BetaLijkl: Beta functions of all quartic scalar couplings 
 BetaYijk: Beta functions of all interactions between two fermions and one scalar 
 BetaTijk: Beta functions of all cubic scalar interactions 
 BetaMuij: Beta functions of all bilinear fermion terms 
 BetaBij: Beta functions of all bilinear scalar terms 
 BetaVEV: Beta functions of all VEVs
ですって。

Commands
SMの場合に以下のコマンドを打ってみた。
    [1] MassMatrices[EWSB] フェルミオンの質量が出てきた。

    [2] CalcLoopCorrections[EWSB] tadpole, self-energy を計算してくれるらしいがよくわからない。

    [3] ModelOutput[EWSB, VerticesForLoops -> True] vertex を計算してくれるらしい。

    [4] MakeTeX[] 結果をtexに書いてくれる。pdfにするにはスクリプトを使えと親切なメッセージが表示される。

    しかし、親切なメッセージに従いスクリプトを実行したところ、途中で止まってしまった。Macだからだろうか。? と表示されたので、z と打ったら、止まらずに実行するには r と打て、と表示されたのでそうすると、一応pdfができた。

    できたpdfファイル は途中で終わってしまっているが、RGEがあるのでよし。また、ファインマンルールが図入りで表示されるのは便利かも。

以上。

Tips and questions
[1]When writing down Yukawa couplings, there seems implicit rule. Difine matter fields as 
    FermionFields[[1]] = {q, 3, {uL, dL},     1/6, 2,  3, 1};  
FermionFields[[2]] = {l, 3, {vL, eL},    -1/2, 2,  1, 1};
FermionFields[[3]] = {d, 3, conj[dR],     1/3, 1, -3, 1};
FermionFields[[4]] = {u, 3, conj[uR],    -2/3, 1, -3, 1};
FermionFields[[5]] = {e, 3, conj[eR],       1, 1,  1, 1};

ScalarFields[[1]] =  {H, 1, {Gp, H0},     1/2, 2,  1,  1};
Then the following definition of the Yukawa interaction works
    LagHC = - Yd conj[H].q.d - Ye conj[H].l.e - Yu H.q.u;
But the following returns the error message, hyper charge is not conserved.
    LagHC = - Yd H.q.d - Ye H.l.e - Yu conj[H].q.u;
Why?


[2]When writing down Higgs mass terms, the following does not work 

    M1^2 conj[H].H + M22
Perhaps, we can not use ^2 . So we have to use, say, 
    M12 conj[H].H + M22
[3] Avoid to use S as particle name. This is for class name.

[4] Avoid to use A as OutputName in particles.m . This is for photon's OutputName.

[5] Avoid to use Lambda as a parameter name. This does not work. (Perhaps this has a special meaning in sarah.) Instead, you can use \[Lambda] or LambdaH and so on.

[6] Don't do MakeSPheno[] in /Models/SM/CKM/ . (You can do it after you copy the file /SM/SPheno.m into /SM/CKM/ ) It does not work. Perhaps we just want to see CKM effect in SPheno's calculation. Then do MakeSPheno[] in /Models/SM/ . It works, namely CKM effects are taken into account by SPheno.
(The author of Sarah guarantees this. See here ).

[7] In the model file, if the Lagrangian is too long, then we write, for example 

    
LagHC = Lambda5/2 conj[H2].H1.conj[H2].H1 \
	 + Lambda6 conj[H1].H1.conj[H1].H2 \
	 + Lambda7 conj[H2].H2.conj[H1].H2 ;
There is an implicit rule. "Do not use space after \ ".

[8] Do not put tadpole terms in the Lagrangian, such as L = c S, where c is a couping and S is a scalar field. If you put this term, sarah does not evaluate vertices including scalar fields.

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