int main(int argc, char * argv[]) {
TApplication app("app", &argc, argv);
plottingEngine.SetDefaultStyle();
const bool debug = true;
// Load the field map.
ComponentAnsys123* fm = new ComponentAnsys123();
const std::string efile = "ELIST.lis";
const std::string nfile = "NLIST.lis";
const std::string mfile = "MPLIST.lis";
const std::string sfile = "PRNSOL.lis";
fm->Initialise(efile, nfile, mfile, sfile, "mm");
fm->EnableMirrorPeriodicityX();
fm->EnableMirrorPeriodicityY();
fm->PrintRange();
// Dimensions of the GEM
const double pitch = 0.014;
const double kapton = 50.e-4;
const double metal = 5.e-4;
const double outdia = 70.e-4;
const double middia = 50.e-4;
const bool plotField = false;
if (plotField) {
ViewField* fieldView = new ViewField();
fieldView->SetComponent(fm);
fieldView->SetPlane(0., -1., 0., 0., 0., 0.);
fieldView->SetArea(-pitch / 2., -0.02, pitch / 2., 0.02);
fieldView->SetVoltageRange(-160., 160.);
TCanvas* cF = new TCanvas();
fieldView->SetCanvas(cF);
fieldView->PlotContour();
}
// Setup the gas.
MediumMagboltz* gas = new MediumMagboltz();
gas->SetComposition("ar", 70., "co2", 30.);
gas->SetTemperature(293.15);
gas->SetPressure(760.);
gas->EnableDebugging();
gas->Initialise();
gas->DisableDebugging();
// Set the Penning transfer efficiency.
const double rPenning = 0.57;
const double lambdaPenning = 0.;
gas->EnablePenningTransfer(rPenning, lambdaPenning, "ar");
// Load the ion mobilities.
gas->LoadIonMobility("IonMobility_Ar+_Ar.txt");
// Associate the gas with the corresponding field map material.
const int nMaterials = fm->GetNumberOfMaterials();
for (int i = 0; i < nMaterials; ++i) {
const double eps = fm->GetPermittivity(i);
if (fabs(eps - 1.) < 1.e-3) fm->SetMedium(i, gas);
}
fm->PrintMaterials();
// Create the sensor.
Sensor* sensor = new Sensor();
sensor->AddComponent(fm);
sensor->SetArea(-5 * pitch, -5 * pitch, -0.03,
5 * pitch, 5 * pitch, 0.03);
AvalancheMicroscopic* aval = new AvalancheMicroscopic();
aval->SetSensor(sensor);
AvalancheMC* drift = new AvalancheMC();
drift->SetSensor(sensor);
drift->SetDistanceSteps(2.e-4);
const bool plotDrift = true;
ViewDrift* driftView = new ViewDrift();
if (plotDrift) {
driftView->SetArea(-2 * pitch, -2 * pitch, -0.02,
2 * pitch, 2 * pitch, 0.02);
// Plot every 10 collisions (in microscopic tracking).
aval->SetCollisionSteps(10);
aval->EnablePlotting(driftView);
drift->EnablePlotting(driftView);
}
// Histograms
int nBinsGain = 100;
double gmin = 0.;
double gmax = 100.;
TH1F* hElectrons = new TH1F("hElectrons", "Number of electrons",
nBinsGain, gmin, gmax);
TH1F* hIons = new TH1F("hIons", "Number of ions",
nBinsGain, gmin, gmax);
int nBinsChrg = 100;
TH1F* hChrgE = new TH1F("hChrgE", "Electrons on plastic",
nBinsChrg, -0.5e4 * kapton, 0.5e4 * kapton);
TH1F* hChrgI = new TH1F("hChrgI", "Ions on plastic",
nBinsChrg, -0.5e4 * kapton, 0.5e4 * kapton);
double sumIonsTotal = 0.;
double sumIonsDrift = 0.;
double sumIonsPlastic = 0.;
double sumElectronsTotal = 0.;
double sumElectronsPlastic = 0.;
double sumElectronsUpperMetal = 0.;
double sumElectronsLowerMetal = 0.;
double sumElectronsTransfer = 0.;
double sumElectronsOther = 0.;
const int nEvents = 10;
for (int i = nEvents; i--;) {
if (debug || i % 10 == 0) std::cout << i << "/" << nEvents << "\n";
// Randomize the initial position.
const double smear = pitch / 2.;
double x0 = -smear + RndmUniform() * smear;
double y0 = -smear + RndmUniform() * smear;
double z0 = 0.025;
double t0 = 0.;
double e0 = 0.1;
aval->AvalancheElectron(x0, y0, z0, t0, e0, 0., 0., 0.);
int ne = 0, ni = 0;
aval->GetAvalancheSize(ne, ni);
hElectrons->Fill(ne);
hIons->Fill(ni);
const int np = aval->GetNumberOfElectronEndpoints();
double xe1, ye1, ze1, te1, e1;
double xe2, ye2, ze2, te2, e2;
double xi1, yi1, zi1, ti1;
double xi2, yi2, zi2, ti2;
int status;
for (int j = np; j--;) {
aval->GetElectronEndpoint(j, xe1, ye1, ze1, te1, e1,
xe2, ye2, ze2, te2, e2, status);
sumElectronsTotal += 1.;
if (ze2 > -kapton / 2. && ze2 < kapton / 2.) {
hChrgE->Fill(ze2 * 1.e4);
sumElectronsPlastic += 1.;
} else if (ze2 >= kapton / 2. && ze2 <= kapton / 2. + metal) {
sumElectronsUpperMetal += 1.;
} else if (ze2 <= -kapton / 2. && ze2 >= -kapton / 2. - metal) {
sumElectronsLowerMetal += 1.;
} else if (ze2 < -kapton / 2. - metal) {
sumElectronsTransfer += 1.;
} else {
sumElectronsOther += 1.;
}
drift->DriftIon(xe1, ye1, ze1, te1);
drift->GetIonEndpoint(0, xi1, yi1, zi1, ti1,
xi2, yi2, zi2, ti2, status);
if (zi1 < 0.01) {
sumIonsTotal += 1.;
if (zi2 > 0.01) sumIonsDrift += 1.;
}
if (zi2 > -kapton / 2. && zi2 < kapton / 2.) {
hChrgI->Fill(zi2 * 1.e4);
sumIonsPlastic += 1.;
}
}
}
double fFeedback = 0.;
if (sumIonsTotal > 0.) fFeedback = sumIonsDrift / sumIonsTotal;
std::cout << "Fraction of ions drifting back: " << fFeedback << "\n";
const double neMean = hElectrons->GetMean();
std::cout << "Mean number of electrons: " << neMean << "\n";
const double niMean = hIons->GetMean();
std::cout << "Mean number of ions: " << niMean << "\n";
std::cout << "Mean number of electrons on plastic: "
<< sumElectronsPlastic / nEvents << "\n";
std::cout << "Mean number of ions on plastic: "
<< sumIonsPlastic / nEvents << "\n";
std::cout << "Electron endpoints:\n";
const double fUpperMetal = sumElectronsUpperMetal / sumElectronsTotal;
const double fPlastic = sumElectronsPlastic / sumElectronsTotal;
const double fLowerMetal = sumElectronsLowerMetal / sumElectronsTotal;
const double fTransfer = sumElectronsTransfer / sumElectronsTotal;
const double fOther = sumElectronsOther / sumElectronsTotal;
std::cout << " upper metal: " << fUpperMetal * 100. << "%\n";
std::cout << " plastic: " << fPlastic * 100. << "%\n";
std::cout << " lower metal: " << fLowerMetal * 100. << "%\n";
std::cout << " transfer: " << fTransfer * 100. << "%\n";
std::cout << " other: " << fOther * 100. << "%\n";
TCanvas* cD = new TCanvas();
const bool plotGeo = true;
if (plotGeo && plotDrift) {
// Build the geometry in Root.
TGeoManager* geoman = new TGeoManager("world", "geometry");
TGeoMaterial* matVacuum = new TGeoMaterial("Vacuum", 0, 0, 0);
TGeoMedium* medVacuum = new TGeoMedium("Vacuum", 1, matVacuum);
TGeoMaterial* matKapton = new TGeoMaterial("Kapton", 12, 6, 1.42);
TGeoMedium* medKapton = new TGeoMedium("Kapton", 2, matKapton);
TGeoMaterial* matCopper = new TGeoMaterial("Copper", 63, 29, 8.94);
TGeoMedium* medCopper = new TGeoMedium("Copper", 3, matCopper);
TGeoVolume* volTop = geoman->MakeBox("TOP",
medVacuum, pitch, pitch, 0.02);
volTop->SetVisibility(0);
TGeoBBox* shpKapton = new TGeoBBox("K", pitch / 2.,
pitch / 2.,
kapton / 2.);
TGeoPcon* shpHole = new TGeoPcon("H", 0., 360., 3);
shpHole->DefineSection(0, -kapton / 2., 0., outdia / 2.);
shpHole->DefineSection(1, 0., 0., middia / 2.);
shpHole->DefineSection(2, kapton / 2., 0., outdia / 2.);
TGeoCompositeShape* shpGem = new TGeoCompositeShape("G", "K - H");
TGeoVolume* volKapton = new TGeoVolume("Kapton", shpGem, medKapton);
volKapton->SetLineColor(kGreen);
volKapton->SetTransparency(50);
TGeoBBox* shpMetal = new TGeoBBox("M", pitch / 2.,
pitch / 2.,
metal / 2.);
TGeoTube* shpTube = new TGeoTube("T", 0., outdia / 2., metal / 2.);
TGeoCompositeShape* shpElectrode = new TGeoCompositeShape("E", "M - T");
TGeoVolume* volElectrode = new TGeoVolume("Electrode",
shpElectrode, medCopper);
volElectrode->SetLineColor(kBlue);
volElectrode->SetTransparency(50);
TGeoVolumeAssembly* volGem = new TGeoVolumeAssembly("Gem");
const double shift = 0.5 * (metal + kapton);
volGem->AddNode(volKapton, 1);
volGem->AddNode(volElectrode, 2, new TGeoTranslation(0., 0., shift));
volGem->AddNode(volElectrode, 3, new TGeoTranslation(0., 0., -shift));
volTop->AddNode(volGem, 1);
volTop->AddNode(volGem, 2, new TGeoTranslation(-pitch, 0., 0.));
volTop->AddNode(volGem, 3, new TGeoTranslation(+pitch, 0., 0.));
volTop->AddNode(volGem, 4,
new TGeoTranslation(-pitch / 2., sqrt(3) * pitch / 2., 0.));
volTop->AddNode(volGem, 5,
new TGeoTranslation(+pitch / 2., sqrt(3) * pitch / 2., 0.));
volTop->AddNode(volGem, 6,
new TGeoTranslation(-pitch / 2., -sqrt(3) * pitch / 2., 0.));
volTop->AddNode(volGem, 7,
new TGeoTranslation(+pitch / 2., -sqrt(3) * pitch / 2., 0.));
geoman->SetVerboseLevel(0);
geoman->SetTopVolume(volTop);
geoman->CloseGeometry();
geoman->CheckOverlaps(0.1e-4);
geoman->SetNmeshPoints(100000);
cD->cd();
geoman->GetTopVolume()->Draw("ogl");
}
if (plotDrift) {
driftView->SetCanvas(cD);
driftView->Plot();
}
const bool plotHistogram = true;
if (plotHistogram) {
TCanvas* cH = new TCanvas("cH", "Histograms", 800, 700);
cH->Divide(2, 2);
cH->cd(1);
hElectrons->Draw();
cH->cd(2);
hIons->Draw();
cH->cd(3);
hChrgE->Draw();
cH->cd(4);
hChrgI->Draw();
}
app.Run(kTRUE);
}
