// T. Kondo, 2010.4.19  updated 2020.8.7


void plot_VFD_Neff()
{

TCanvas *c1=new TCanvas("c1","canvas",0,0,700,500);
c1->SetGrid();
c1->SetTopMargin(0.08);
c1->SetBottomMargin(0.12);
int n=0;
char line[200];
double VFD[9]={-70.,-30.,30.,70.}, X[9], Ey[3][9], Rho[9]={};
double Neff[9]={-1.105e12,-0.471e12, 0.414e12, 0.968e12};
double xmin=-80., xmax=80.;
double ymin=-1.2e12, ymax=1.2e12;
double VFDM[50], NeffFDM[50];
for (int i=0; i<15; i++){
  VFDM[i]  = i*10. - 70.;
// Neff = = VFD*2*iepsilon(Si)*epsilon0/(q0*d**2)
  NeffFDM[i]= 1.592e10*VFDM[i];
}

TGraph *h1, *h2, *h3;
TLegend *leg;
h1 = new TGraph(4,VFD,Neff);
h2 = new TGraph(15,VFDM,NeffFDM);
h2->SetLineStyle(2);
h1->GetXaxis()->SetTitle("Full Depletion Voltage V_{FD} [V]");
h1->GetXaxis()->SetTitleOffset(1.0);
h1->GetYaxis()->SetTitle("Space charge density Neff [cm^{-3}]");
h1->GetXaxis()->SetLimits(xmin,xmax);
h1->SetMaximum(ymax);
h1->SetMinimum(ymin);
h1->Draw("ALP");
h2->Draw("SAME L");
leg=new TLegend(0.20,0.70,0.65,0.8);
leg->AddEntry(h1,"Finite Element Model","lp");
leg->AddEntry(h2,"Flat Diode Model","l");
leg->SetBorderSize(0);
leg->Draw();

c1->Print("VFD_Neff.png");
return;
}