PMT.cc

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#include "PMT.h"
 
void PMT::PrintChargeSpectrumPMT(float windowlow, float windowhi, float start, float end, float rangestart, float rangeend, int nbins) {
 
    PrintChargeSpectrumPMT_cnt++;
 
    string ctitle("charge spectra PMT" + to_string(PrintChargeSpectrumPMT_cnt));
    TCanvas* chargec = new TCanvas(ctitle.c_str(), ctitle.c_str(), 600, 400);
    Helpers::SplitCanvas(chargec, active_channels, plot_active_channels);
 
    int current_canvas = 0;
 
    for (int i = 0; i < nchannels; i++) {
        if (PlotChannel(i)) {
            current_canvas++;
 
            TH1F* his;
            his = ChargeSpectrum(i, windowlow, windowhi, start, end, rangestart, rangeend, nbins);
            if (windowlow + windowhi > 0.) his->GetXaxis()->SetTitle("integral in mV#timesns");
            else his->GetXaxis()->SetTitle("amplitude in mV");
            chargec->cd(current_canvas);
 
            his->GetYaxis()->SetTitle("#Entries");
            his->GetXaxis()->SetTitle("integral in mV#timesns");
            his->Draw();
            stringstream allname; allname << his->GetEntries() << " entries";
            his->SetTitle(allname.str().c_str());
 
            TString name(Form("ChargeSpectrumPMT channel_%02d", active_channels[i]));
            root_out->WriteObject(his, name.Data());
 
            // fit sum of two gaussians
            // estimate starting values of fit by fitting only one gauss
            auto gauss = new TF1("gauss", "gaus", rangestart, rangeend);
            TFitResultPtr fres_est = his->Fit(gauss, "QRSL");
            // now use these fit results to fit the sum of two gauss
            auto two_gauss = new TF1("two gaussians", "gaus(0)+gaus(3)", rangestart, rangeend); two_gauss->SetTitle("Sum of two gauss");
            two_gauss->SetParameters(fres_est->Parameter(0) * .95, fres_est->Parameter(1) * .95, fres_est->Parameter(2) * .95, fres_est->Parameter(0) * .3, fres_est->Parameter(1) * 1.05, fres_est->Parameter(2) * .85); // factors are pretty much random
            two_gauss->SetParName(0, "A_{pedestal}");
            two_gauss->SetParName(1, "#mu_{pedestal}");
            two_gauss->SetParName(2, "#sigma_{pedestal}");  two_gauss->SetParLimits(2, 1e-9, 1e3);
            two_gauss->SetParName(3, "A_{SPE}");
            two_gauss->SetParName(4, "#mu_{SPE}");
            two_gauss->SetParName(5, "#sigma_{SPE}");       two_gauss->SetParLimits(5, 1e-9, 1e3);
 
            if (!PrintChargeSpectrumPMT_pars.empty()) {
                for (int j = 0; j < static_cast<int>(PrintChargeSpectrumPMT_pars.size()); j++) two_gauss->SetParameter(j, PrintChargeSpectrumPMT_pars[j]);
            }
 
            //two_gauss->SetLineColor(4);
            TFitResultPtr fresults = his->Fit(two_gauss, "RSL");
            fit_results.push_back(fresults);
 
            two_gauss->Draw("same");
 
            auto pedestal = new TF1("pedestal", "gaus", rangestart, rangeend); pedestal->SetTitle("pedestal");
            pedestal->SetParameters(fresults->Parameter(0), fresults->Parameter(1), fresults->Parameter(2));
            pedestal->SetLineColor(3);
            pedestal->Draw("same");
 
            auto pepeak = new TF1("pepeak", "gaus", rangestart, rangeend); pepeak->SetTitle("pepeak");
            pepeak->SetParameters(fresults->Parameter(3), fresults->Parameter(4), fresults->Parameter(5));
            pepeak->SetLineColor(4);
            pepeak->Draw("same");
 
            gPad->BuildLegend();
        }
    }
 
    chargec->Update();
    root_out->WriteObject(chargec, "ChargeSpectraPMT");
}
 
void PMT::PrintChargeSpectrumPMTthreshold(float windowlow, float windowhi, float rangestart, float rangeend, int nbins, double threshold, bool calculate_SiPM_DCR) {
 
    PrintChargeSpectrumPMTthreshold_cnt++;
 
    gStyle->SetOptStat(0); // 11 is title + entries
 
    // show fraction of events above 0.5 pe charge = pedestal + gain/2
    // dark count rate for SiPMs (currently only automated for fit function Fitf)
    // need to call the SiPM fit function before this one for this functionality
    bool use_fit_result_for_threshold = false;
    if (threshold == 999) {
        calculate_SiPM_DCR = true;
        use_fit_result_for_threshold = true;
    }
 
    string unit(" mV");
    string title("amplitude in mV"); // amplitude spectrum not good for fitting, will be biased
    if (windowlow + windowhi > 0.) {
        unit = " mV#timesns";
        title = "integral in mV#timesns";
    }
    string ctitle("charge spectra PMT threshold" + to_string(PrintChargeSpectrumPMTthreshold_cnt));
    TCanvas* chargec = new TCanvas(ctitle.c_str(), ctitle.c_str(), 600, 400);
    Helpers::SplitCanvas(chargec, active_channels, plot_active_channels);
 
    int current_canvas = 0;
    double threshold_bin_center = 0;
 
    for (int i = 0; i < nchannels; i++) {
        if (PlotChannel(i)) {
 
            if (use_fit_result_for_threshold) threshold = fit_results[current_canvas]->Parameter(6) + fit_results[current_canvas]->Parameter(5) / 2.;
 
            chargec->cd(++current_canvas);
 
            TH1F* his;
            his = ChargeSpectrum(i, windowlow, windowhi, rangestart, rangeend, rangestart, rangeend, nbins);
            his->GetXaxis()->SetTitle(title.c_str());
            his->GetYaxis()->SetTitle("#Entries");
            his->Draw();
            stringstream allname; allname << his->GetEntries() << " entries";
            his->SetTitle(allname.str().c_str());
 
            auto his_lo = (TH1F*)his->Clone();
            his_lo->GetXaxis()->SetRange(his_lo->GetXaxis()->FindBin(rangestart), his_lo->GetXaxis()->FindBin(threshold));
            his_lo->SetLineColor(2);
            his_lo->SetFillColor(2);
            his_lo->Draw("LF2 same");
 
            stringstream lonamefrac;
            stringstream lonamerate;
            lonamefrac << 100. * his->Integral(his->GetXaxis()->FindBin(rangestart), his->GetXaxis()->FindBin(threshold)) / his->GetEntries() << "% <= " << threshold << unit;
            lonamerate << "<0.5 pe=" << threshold << unit << " -> " << his->Integral(his->GetXaxis()->FindBin(rangestart), his->GetXaxis()->FindBin(threshold)) / his->GetEntries() / (1.e-3 * (rangeend - rangestart)) << " MHz";
            cout << "\n" << lonamerate.str().c_str() << endl;
            cout << "\n" << lonamefrac.str().c_str() << endl;
            his_lo->SetTitle(lonamerate.str().c_str());
            if (!calculate_SiPM_DCR) his_lo->SetTitle(lonamefrac.str().c_str());
 
            auto his_hi = (TH1F*)his->Clone();
            his_hi->GetXaxis()->SetRange(his_hi->GetXaxis()->FindBin(threshold), his_lo->GetXaxis()->FindBin(rangeend));
            his_hi->SetLineColor(1);
            his_hi->SetFillColor(1);
            his_hi->Draw("LF2 same");
 
            stringstream hinamefrac;
            stringstream hinamerate;
            hinamefrac << 100. * his->Integral(his->GetXaxis()->FindBin(threshold) + 1, his->GetXaxis()->FindBin(rangeend)) / his->GetEntries() << "% > " << threshold << unit;
            hinamerate << ">0.5 pe=" << threshold << unit << " -> " << his->Integral(his->GetXaxis()->FindBin(threshold) + 1, his->GetXaxis()->FindBin(rangeend)) / his->GetEntries() / (1.e-3 * (rangeend - rangestart)) << " MHz";
            cout << "\n" << hinamerate.str().c_str() << endl;
            cout << "\n" << hinamefrac.str().c_str() << endl;
            his_hi->SetTitle(hinamerate.str().c_str());
            if (!calculate_SiPM_DCR) his_hi->SetTitle(hinamefrac.str().c_str());
 
            gPad->BuildLegend();
 
            threshold_bin_center = his->GetXaxis()->GetBinCenter(his->GetXaxis()->FindBin(threshold) + 1);
            cout << "\n PMT charge spectrum is counting events above threshold from bin center >= " << threshold_bin_center << unit << " for a threshold setting of " << threshold << unit << "\n\n";
        }
    }
 
    chargec->Update();
    root_out->WriteObject(chargec, "ChargeSpectraPMTthreshold");
}