adding implicit DeltaLambda parameter to EXTPAR[101]

which adds the term

  DeltaLambda * Log(MZ/MS) / (4 Pi)^4

to the matching condition for lambda.  It will be used to estimate the
uncertainty coming from the matching condition in the tower.

meta/FlexibleSUSY.m

@@ -151,6 +151,8 @@ FlexibleSUSY model file (FlexibleSUSY.m).
 FSFermiConstant;
 FSMassW;
 
+DeltaLambda;
+
 {FSHiggs, FSHyperchargeCoupling,
  FSLeftCoupling, FSStrongCoupling, FSVEVSM1, FSVEVSM2, FSNeutralino,
  FSChargino, FSNeutralinoMM, FSCharginoMinusMM, FSCharginoPlusMM,
@@ -1732,6 +1734,10 @@ corresponding tadpole is real or imaginary (only in models with CP
            SARAH`Xip = 1;
            SARAH`rMS = SelectRenormalizationScheme[FlexibleSUSY`FSRenormalizationScheme];
 
+           If[Head[SARAH`EXTPAR] === List,
+              AppendTo[SARAH`EXTPAR, {101, DeltaLambda}];,
+              SARAH`EXTPAR = {{101, DeltaLambda}};
+             ];
            inputParameters = DeleteDuplicates[{#, GuessInputParameterType[#]}& /@ ((#[[2]])& /@ Utils`ForceJoin[SARAH`MINPAR, SARAH`EXTPAR])];
            Parameters`SetInputParameters[(#[[1]])& /@ inputParameters];
 

templates/SM_matching.cpp.in

@@ -52,6 +52,7 @@ void @ModelName@_SM_matching::match_high_to_low_scale_model(SM_mass_eigenstates&
 {
    const auto model_pole_mass_order = model.get_pole_mass_loop_order();
    const auto sm_pole_mass_order = sm.get_pole_mass_loop_order();
+   const auto DeltaLambda = INPUTPARAMETER(DeltaLambda);
 
    model.set_pole_mass_loop_order(1);
    sm.set_pole_mass_loop_order(1);
@@ -65,7 +66,10 @@ void @ModelName@_SM_matching::match_high_to_low_scale_model(SM_mass_eigenstates&
    sm.solve_ewsb_one_loop();
    sm.calculate_Mhh_pole();
 
-   sm.set_Lambdax((Sqr(model.get_physical().M@HiggsBoson_0@) - Sqr(sm.get_physical().Mhh) + Sqr(sm.get_Mhh()))/Sqr(sm.get_v()));
+   const double MZ = (sm.get_physical().MVZ != 0. ? sm.get_physical().MVZ : sm.get_MVZ());
+
+   sm.set_Lambdax((Sqr(model.get_physical().M@HiggsBoson_0@) - Sqr(sm.get_physical().Mhh) + Sqr(sm.get_Mhh()))/Sqr(sm.get_v())
+                  + DeltaLambda*twoLoop*Log(MZ/model.get_scale()));
 
    model.set_pole_mass_loop_order(model_pole_mass_order);
    sm.set_pole_mass_loop_order(sm_pole_mass_order);