LB Feb 2017 Energy Efficiency Calculations
Theoretical Activities
Na-22, 9.427micro Ci on July 1, 2008, half life 2.602 +/- 0.002 years, 99.937% for 1274.52 and 178.8 for 511 line , activity in March 31, 2016 =1.196micro Ci
- = for the 1274 line
- = for the 511 line
Cs-137, 661.660 line, 85.21% * 1.066micro Ci on July 1, 2008, half life 30.0 +/- 0.2 yrs, Feb 4, 2017 activity = 0.891micro Ci expected rate for 661 line
- =
Mn-54, 11.77 microCi on July 1, 2008, half life =312.20 +/- 0.07 days, 99.975% intensity on 834.826 , March 31, 2016 activity =0.02328micro Ci
- = for the 834 line
Co-60, 10.42micro Ci July 1, 2008, half life 5.271 +/- 0.001 years, 99.0 % for 1173.237 and 99.9824 % for 1332.501, March 31, 2016 activity=3.759micro Ci
- = for the 1173 line
- = for the 1332 line
Ba-133, 9.821 uCi on 04-15-07 with a half life of 10.51 years 62.05% for the 356 line,
- = for the 356 keV line
Actual Activites
This is an example of the method that will be used to find the activities in the calibrated source's spectra
The line of interest in Cs-137 the 661.7 line.
Using the program BackgroundSubtract.C in /data/IAC/Se/Feb_2017_Efficiency/Energy_Efficiency and the root command
BackgroundSubtract("r5818.root","r5891.root",412,3369);
The 661.7 keV line can be seen
Note that the range along the x-axis is [640:680] and the integral is 208.3.
Taking the ratio of the rate seen in the detector and the theoretical rate calculated above, one can arrive at a detector efficiency of 0.7%
The rest of the data is on the wiki page
Energy Efficiencies
Below is a table with the calculated efficiencies
Run | Source | Energy (keV) | Expected Rate (Hz) | ROOT Window | HpGe Rate (Hz) | HpGe X-Cool Detector Efficiency (%) |
r5818 | Cs-137 | 661.7 | 28091.2 | [640:680] | 208.3 | 0.7 |
r5871 | Ba-133 | 356 | 118236.28 | [340:376] | 150.6 | 0.13 |
r5820 | Na-22 | 511 | 79122.6 | [480:540] | 278.6 | 0.4 |
r5820 | Na-22 | 1274 | 44224 | [1220:1320] | 95.89 | 0.2 |
r5896 | Mn-54 | 834 | 861.1 | [800:860] | 7.611 | 0.88 |
r5822 | Co-60 | 1173 | 137692.17 | [1140:1200] | 159.1 | 0.12 |
r5822 | Co-60 | 1332.5 | 139058.52 | [1300:1360] | 134.7 | 0.10 |
Detector B
Theoretical Activities
Na-22, 1.146 uCi on July 1, 2008, half life 2.602 +/- 0.002 years, 99.937% for 1274.52 and 178.8% for 511 line , activity in February 24, 2017 =0.082 uCi
- = for the 1274 line
- = for the 511 line
Cs-137, 661.660 line, 85.21% * 1.066micro Ci on July 1, 2008, half life 30.0 +/- 0.2 yrs, March 31, 2016 activity = 0.891micro Ci expected rate for 661 line
- =
Mn-54, 11.77 microCi on July 1, 2008, half life =312.20 +/- 0.07 days, 99.975% intensity on 834.826 , March 31, 2016 activity =0.02328micro Ci
- = for the 834 line
Co-60, 10.42micro Ci July 1, 2008, half life 5.271 +/- 0.001 years, 99.0 % for 1173.237 and 99.9824 % for 1332.501, March 31, 2016 activity=3.759micro Ci
- = for the 1173 line
- = for the 1332 line
Ba-133, 9.821 uCi on 04-15-07 with a half life of 10.51 years 62.05% for the 356 line,
- = for the 356 keV line