Run6980 Y88

Photon Lines

Energy (keV)	Relative Intensity
850.6	0.065
898.042	93.7
1382.2	0.021
1836.063	99.2
2734.0	0.71
3219.7	0.0070

E(γ) Coincidence

  850.6	898.042, 1836.063, 2734.0
  850.6	898.042, 1836.063, 2734.0
  898.042	850.6, 850.6, 1836.063
  898.042	1836.063
 1382.2	1836.063
 1382.2	1836.063
 1836.063	850.6, 850.6, 898.042, 898.042, 1382.2, 1382.2
 2734.0	850.6, 850.6

Calibration

ntuple->Draw("ADC3*1.29679-127.215 >>(2200,0,4400)")

ntuple->Draw("ADC7*0.595486-52.2669 >>(2200,0,4400)")

Singles Run 6978

Coincidence Lines

Run	Description
6978	OR mode using Y-88 sample # 130113-004 , post amp at 20, rate is 695 Hz, CFD's still at 12 mV for NaI detector and 10 mV for HpGe , 4 min 39 sec
6980	AND mode using Y-88 sample # 130113-004 , post amp at 20, rate is Hz, CFD's still at 12 mV for NaI detector and 10 mV for HpGe , min sec, 10 Hz pulser wasn't working for run 6975-6978, it is working for this run

ntuple->Draw("ADC7*0.595486-52.2669 >>r6978(2200,0,4400)") TH1F *r6978HpGeN=new TH1F("r6978HpGeN","r6978HpGeN",2200,0,4400) r6978HpGeN->Add(r6978,0.003584229);

ntuple->Draw("ADC7*0.595486-52.2669 >>r6980(2200,0,4400)") TH1F *r6980HpGeN=new TH1F("r6980HpGeN","r6980HpGeN",2200,0,4400) r6980HpGeN->Add(r6980,0.000012405);

overlaying two plots

r6978HpGeN->Draw();
Float_t rightmax = 1.1*r6980HpGeN->GetMaximum();
Float_t scale = gPad->GetUymax()/rightmax;
r6980HpGeN->Scale(scale);
r6980HpGeN->Draw("same");
TGaxis *axis = new TGaxis(gPad->GetUxmax(),gPad->GetUymin(),gPad->GetUxmax(), gPad->GetUymax(),0,rightmax,510,"+L");
axis->SetLineColor(kRed);
axis->SetLabelColor(kRed);
axis->Draw();

The coincidence rate is a factor of 20 lower than the Singles rate

A gaussian fit to the above TDC spectrum yields a mean of 114 nsec and a Sigma of 143 nsec.

898 keV in HpGe with a cut around the 1840 keV line in NaI

ntuple->Draw("ADC7*0.595486-52.2669 >>r6978(2200,0,4400)") TH1F *r6978HpGeN=new TH1F("r6978HpGeN","r6978HpGeN",2200,0,4400) r6978HpGeN->Add(r6978,0.003584229);

ntuple->Draw("ADC7*0.595486-52.2669 >>r6980(2200,0,4400)","ADC3>1440 && ADC3 < 1560") TH1F *r6980HpGeN=new TH1F("r6980HpGeN","r6980HpGeN",2200,0,4400) r6980HpGeN->Add(r6980,0.000012405);

overlaying two plots

r6978HpGeN->Draw();
Float_t rightmax = 1.1*r6980HpGeN->GetMaximum();
Float_t scale = gPad->GetUymax()/rightmax;
r6980HpGeN->Scale(scale);
r6980HpGeN->Draw("same");
TGaxis *axis = new TGaxis(gPad->GetUxmax(),gPad->GetUymin(),gPad->GetUxmax(), gPad->GetUymax(),0,rightmax,510,"+L");
axis->SetLineColor(kRed);
axis->SetLabelColor(kRed);
axis->Draw();

1840 keV in HpGe with a cut around the NaI detectors 898 peak

ntuple->Draw("ADC7*0.595486-52.2669 >>r6978(2200,0,4400)") TH1F *r6978HpGeN=new TH1F("r6978HpGeN","r6978HpGeN",2200,0,4400) r6978HpGeN->Add(r6978,0.003584229);

ntuple->Draw("ADC7*0.595486-52.2669 >>r6980(2200,0,4400)","ADC3>780 && ADC3 < 810") TH1F *r6980HpGeN=new TH1F("r6980HpGeN","r6980HpGeN",2200,0,4400) r6980HpGeN->Add(r6980,0.000012405);

overlaying two plots

r6978HpGeN->Draw();
Float_t rightmax = 1.1*r6980HpGeN->GetMaximum();
Float_t scale = gPad->GetUymax()/rightmax;
r6980HpGeN->Scale(scale);
r6980HpGeN->Draw("same");
TGaxis *axis = new TGaxis(gPad->GetUxmax(),gPad->GetUymin(),gPad->GetUxmax(), gPad->GetUymax(),0,rightmax,510,"+L");
axis->SetLineColor(kRed);
axis->SetLabelColor(kRed);
axis->Draw();

There appears to be a chance to detect two 898 keV photons in both detectors in coincidence? Probably one is an accidental.

Is the 1320 keV line real?

The 511 keV seems to always be there as well. Is it an accidental?

PAA_11-11-13#Y-88_coincidence_lines