Run6973 BckGrd

Singles backgrounds

Singles back ground sources

Tl-208: 277, 583, 860

Pb-214: 241, 295, 351

Bi-214: 609, 1120, 1238, 1764

Run 6973

run time recorded by 10 Hx clock into scaler channel 5

5976273-66=5976207/10 = 59762.07 seconds = 166 hrs = 6.9 days

At event number 1941300 the scaler reads the same value, I think the DAQ failed right when the HV on the HpGe tripped.

The HpGe detector warmed up during the run after about Event Number 1916000, you can tell the HV tripped because ADC7 starts loose events above 1500 channels after EventNumber >1910300

compare the plots

ntuple->Draw("ADC7 >>(1100,0,4400)","EventNumber>1941300 && EventNumber < 2000000")

ntuple->Draw("ADC7 >>(1100,0,4400)","EventNumber>1901300 && EventNumber < 2000000")

The following lines were observed by the HpGe detector.

387, 583, 609, 1273, 1456, 1591, 2103

NaI 511 coincidence cut

Place a cut around the 511 keV photons seen in the NaI detector yields the following lines observed by the HpGe detector as shown below.

(386, 438, 491, 511, 582, 950, 1255, 1273, 1591, 2103 keV)

[math]{152 \atop \; }Eu \rightarrow {152 \atop \; }Sm^* + e^+ \rightarrow {152 \atop \; }Sm + \gamma[/math] with a half life of 13 years.

gamma lines are at : 386, 493

NaI 2103 Coincidence cut

Place a cut around the 2103 keV photons seen in the NaI detector yields a 511 and a 583 keV line observed by the HpGe detector as shown below.

A line at 388 keV

Possible Isotopes

U-235 (388 - 142,64.5)

Cf-249 (many coincidence lines)

A clear 511 line

NaI cut on 2100 keV intensifies 511 keV line,

ntuple->Draw("ADC7*0.604262-54.0539-ADC7*ADC7*5.62792e-07 >>(2200,0,4400)","ADC3>1600 & ADC3<1800")

A line at 609 keV

Possible isotopes

Pa-231

A line at 1273 keV

A line at 1593 keV

A line at 2105 keV

PAA_11-11-13#Background_coincidence_lines