// ROOT macro to find peaks (GERDA)

// Discard all bad events using a TEventList

void peakAnalysis( string filename2 , string filenamelist ) {

TFile * file0 = new TFile(filename2.c_str());

TFile * file1 = new TFile(filenamelist.c_str());

TTree * tree = (TTree*)file0->Get("tree");

TEventList * listsel = (TEventList*)file1->Get("listofselected");

TCanvas * can = new TCanvas( "canPeaks" , "Peak Analysis" , 7500 , 5500 , 900 , 600 );

//can->SetLogy();

can->SetGrid();

can->cd();

tree->SetEventList(listsel);

tree->Draw("GEMDEnergyGauss_1.energy[0]>>htemp(10000,10000,10000)");

TH1D * spectrum = (TH1D*)gDirectory->Get("htemp");

spectrum->SetTitle("Energy Spectrum");

spectrum->SetXTitle("Energy [keV]");

spectrum->SetYTitle("Counts");

//spectrum->SetStats(kFALSE);

TSpectrum analyzer( 8 , 2 );

// arg1: max number of peaks

// arg2: resolution between peaks

analyzer.Search( spectrum , 2 , "" , 0.0025);

// arg2: sigma of the searched peaks

// arg3: options

// arg4: peaks with amplitude less than threshold*highest_peak are discarded

vector<double> peaks;

for ( int i = 0 ; i < analyzer.GetNPeaks() ; i++ ) {

peaks.push_back(analyzer.GetPositionX()[i]);

}

sort(peaks.begin(),peaks.end());

cout << endl << "########## PEAKS ##########" << endl;

for ( int i = 0 ; i < peaks.size() ; i++ ) cout << i+1 << "\t" << peaks.at(i) << endl;

cout << "###########################" << endl << endl;

if ( peaks.size() < 6 ) {

cout << "ERROR: Not enough peaks found, try to modify TSpectrum parameters.\n\n";

return;

}

ofstream file("calib.txt");

file << "// calibration" << endl

<< "// ch\tkeV" << endl

<< peaks.at(0) << "\t1460.882 // 40K" << endl

<< peaks.at(1) << "\t1512.700 // 212Bi" << endl

<< peaks.at(2) << "\t1592.515 // 208Tl (double escape)" << endl

<< peaks.at(3) << "\t1620.738 // 212Bi" << endl

<< peaks.at(5) << "\t2103.513 // 208Tl (single escape)" << endl

<< peaks.at(6) << "\t2614.511 // 208Tl";

return;

}