diff --git a/NPLib/Physics/NPFissionDecay.cxx b/NPLib/Physics/NPFissionDecay.cxx
index e476e2292f2ae4a252b3fa5003363c3106d77221..5b7cb1f7a1b58985191d8973e0d38796251409d7 100644
--- a/NPLib/Physics/NPFissionDecay.cxx
+++ b/NPLib/Physics/NPFissionDecay.cxx
@@ -92,8 +92,8 @@ bool NPL::FissionDecay::GenerateEvent(string CompoundName, double MEx,double MEK
 
   TVector3 Momentum(MPx,MPy,MPz);
   Momentum.Unit();
-  double Theta = Momentum.Theta();
-  double Phi = Momentum.Phi();
+  double ThetaCN = Momentum.Theta();
+  double PhiCN = Momentum.Phi();
   double Lfis = 0;
 
   m_Compound = NPL::Particle(CompoundName);
@@ -102,7 +102,7 @@ bool NPL::FissionDecay::GenerateEvent(string CompoundName, double MEx,double MEK
   if(m_FissionModelName=="GEF"){
     if(m_FissionModel->IsValid(m_Compound.GetZ(), m_Compound.GetA())){
       worked=true;
-      m_FissionModel->InitCompound(MEx,MEK,Lfis,Theta,Phi);
+      m_FissionModel->InitCompound(MEx,MEK,Lfis,ThetaCN,PhiCN);
       m_FissionModel->Treat();
 
       int Ah = m_FissionModel->GetAffh();
@@ -146,14 +146,17 @@ bool NPL::FissionDecay::GenerateEvent(string CompoundName, double MEx,double MEK
       double Phil   = m_FissionModel->GetPhffl();
       double Phih   = m_FissionModel->GetPhffh();
 
+      TVector3 uxy = TVector3(cos(TMath::Pi()/2-PhiCN), -sin(TMath::Pi()/2-PhiCN), 0);
       TVector3 Momentuml = Pl * TVector3(sin(Thetal)*cos(Phil),
           sin(Thetal)*sin(Phil),
           cos(Thetal));
+      //Momentuml.Rotate(-ThetaCN, uxy);
 
       TVector3 Momentumh = Ph * TVector3(sin(Thetah)*cos(Phih),
           sin(Thetah)*sin(Phih),
           cos(Thetah));
-
+      //Momentumh.Rotate(-ThetaCN, uxy);
+      
       DPx.push_back(Momentuml.X());
       DPx.push_back(Momentumh.X());
       DPy.push_back(Momentuml.Y());
diff --git a/NPSimulation/Detectors/Sofia/SofTofW.cc b/NPSimulation/Detectors/Sofia/SofTofW.cc
index b19731221987ca0e04abf76bba46b3c1fb28c7a2..f4643859d8c48a6ffca53aa21f9dd9a1f3e963cf 100644
--- a/NPSimulation/Detectors/Sofia/SofTofW.cc
+++ b/NPSimulation/Detectors/Sofia/SofTofW.cc
@@ -260,8 +260,8 @@ G4AssemblyVolume* SofTofW::BuildVacuumPipe(){
 
     G4Tubs* tube = new G4Tubs("tube",8.*cm,15*cm,155./2*cm,0,360*deg);
     
-    G4Box* box_int = new G4Box("box_int",25./2*cm,22./2*cm,14.1/2*cm);
-    G4Box* box_ext = new G4Box("box_ext",50./2*cm,50./2*cm,14./2*cm);
+    G4Box* box_int = new G4Box("box_int",22./2*cm,22./2*cm,14.1/2*cm);
+    G4Box* box_ext = new G4Box("box_ext",150./2*cm,150./2*cm,14./2*cm);
 
     G4VSolid* box_subtract = new G4SubtractionSolid("box_subtract",box_ext,box_int,0,G4ThreeVector(0,0,0));
 
diff --git a/Projects/Sofia/sofia.detector b/Projects/Sofia/sofia.detector
index bda4aa6efa56943b2d0d22f8b101feca5460fb93..da3542989588bb5b1d36d1184d039e93df8f4e6b 100644
--- a/Projects/Sofia/sofia.detector
+++ b/Projects/Sofia/sofia.detector
@@ -9,7 +9,7 @@ Target
  Z= 0 m
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 SofTofW
- R= 9 m
+ R= 8 m
  THETA= -9 deg
  PHI= 0 deg
  Build_GLAD= 1
@@ -18,7 +18,7 @@ SofTofW
  Build_VacuumPipe= 1
  VacuumPipeX= 0 cm
  VacuumPipeY= 0 cm
- VacuumPipeZ= 2.4 m
+ VacuumPipeZ= 2.5 m
 %Build_Twin_Music= 0
  %Twin_Music_DistanceFromTarget= 1.5 m
  %Twin_Music_Gas= P10_1atm