# LB Feb 2017 Energy Efficiency Calculations

## Theoretical Activities

Na-22, 10.19 uCi on July 15, 2013, half life 2.602 +/- 0.002 years, 99.937% for 1274.52 and 178.8 for 511 line , activity in Feb 4, 2017 =3.945 uCi

= for the 1274 line
= for the 511 line

Cs-137, 661.660 line, 85.21% * 9.067 uCi on May 1, 2005, half life 30.0 +/- 0.2 yrs, Feb 4, 2017 activity = 6.915 uCi expected rate for 661 line

=

Mn-54, 9.882 uCi on August 1, 2012, half life =312.20 +/- 0.07 days, 99.975% intensity on 834.826 , Feb 12, 2017 activity = 0.25 uCi

= for the 834 line

Co-60, 9.080 uCi July 15, 2013, half life 5.271 +/- 0.001 years, 99.0 % for 1173.237 and 99.9824 % for 1332.501, Feb 4, 2017 activity=5.68 uCi

= 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 218014.0455 [652:672] 339.2 +/- 0.05 0.16 r5871 Ba-133 356 118236.28 [348:364] 286.00 +/- 0.03 0.24 r5820 Na-22 511 260985.42 [490:530] 479.94 +/- 0.42 0,18 r5820 Na-22 1274 145873.0421 [1255:1295] 177.99 +/- 0 0.12 r5896 Mn-54 834 9247.6875 [824:842] 14.93 +/- 0.01 0.16 r5822 Co-60 1173 208058.4 [1160:1190] 274.07 +/- 0 0.13 r5822 Co-60 1332.5 210123.0118 [1320:1350] 259.86 +/- 0 0.12

# 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 =0.114 uCi

= for the 1274 line
= for the 511 line

Cs-137, 661.660 line, 85.21%, 1.066 uCi on July 1, 2008, half life 30.0 +/- 0.2 yrs, Feb 24, 2017 activity = 0.8727 uCi expected rate for 661 line

=

Mn-54, 9.882 uCi on August 1, 2012, half life =312.20 +/- 0.07 days, 99.975% intensity on 834.826 , Feb 24, 2017 activity =0.2435 uCi

= for the 834 line

Ba-133, 1.188 uCi on 07-01-08 with a half life of 10.51 years 62.05% for the 356 line, activity on Feb 24, 2017 is 0.671 uCi

= for the 81 keV line
= for the 356 keV line

There was another Ba-133 source used which had an activity of 9.821 uCi on 4-15-07, using the same half life and the same branching ratio, the activity on Feb 24, 2017 is 5.1219 uCi. The branching ratio for the 356keV line is 62.05% while the branching ratio for the 81 keV line is 32.9%

= for the 81 keV line
= for the 356 keV line

# Actual Activities

The method for calculating the actual activities is the same as above and the plots can be found at LB_Efficiency_Plots_Feb_2017

 Run Source Energy (keV) Position Expected Rate (Hz) ROOT Window HpGe Rate (Hz) Detector B Efficiency (%) Ba133_3.9cm_detB Ba-133 81 3.9cm 8168.083 [76:86] 137.12 +/- 0.6266 1.68 Ba133_3.9cm_detB Ba-133 356 3.9cm 15405.15 [352:360] 191.21 +/- 0.074 1.24 Ba133_4.1cm_detB Ba-133 81 4.1cm 8168.083 [76:86] 137.5 +/- 0.6984 1.68 Ba133_4.1cm_detB Ba-33 356 4.1cm 15405.15 [352:360] 190.44 +/- 0.08 1.24 Ba133_7.9cm_detB Ba-133 81 7.9cm 62348.8887 [76:86] 345.36 +/- 1.32 0.55 Ba133_7.9cm_detB Ba-133 356 7.9cm 117591.1412 [352:360] 494.24 +/- 0.0954 0.42 Ba133_8.1cm_detB Ba-133 81 8.1cm 62348.8887 [76:86] 326.17 +/- 1.20 0.52 Ba133_8.1cm_detB Ba-133 356 8.1cm 117591.1412 [352:360] 482.58 +/- 0.10 0.41 Cs137_3.9cm_detB Cs-137 661 3.9cm 26079.7 [658:666] 182.33 +/- 0.05 0.70 Cs137_4.1cm_detB Cs-137 661 4.1cm 26079.7 [658:666] 175.26 +/- 0.04 0.67 Cs137_7.9cm_detB Cs-137 661 7.9cm 26079.7 [658:666] 64.28 +/- 0.04 0.25 Cs137_8.1cm_detB Cs-137 661 8.1cm 26079.7 [658:666] 65.14 +/- 0.04 0.25 Mn54_3.9cm_detB Mn-54 834 3.9cm 8986.976 [830:838] 54.75 +/- 0.02 0.61 Mn54_4.1cm_detB Mn-54 834 4.1cm 8986.976 [830:838] 52.55 +/- 0.02 0.58 Mn54_7.9cm_detB Mn-54 834 7.9cm 8986.976 [830:838] 18.62 +/- 0.02 0.21 Mn54_8.1cm_detB Mn-54 834 8.1cm 8986.976 [830:838] 17.98 +/- 0.01 0.20 Na22_3.9cm_detB Na-22 511 3.9cm 7541.784 [504:516] 81.74 +/- 0.09 1.08 Na22_3.9cm_detB Na-22 1274 3.9cm 4215.35 [1270:1280] 24.18 +/- 0 0.57 Na22_4.1cm_detB Na-22 511 4.1cm 7541.784 [504:516] 74.71 +/- 0.09 0.99 Na22_4.1cm_detB Na-22 1274 4.1cm 4215.35 [1270:1280] 22.90 +/- 0 0.54 Na22_7.9cm_detB Na-22 511 7.9cm 7541.784 [504:516] 25.55 +/- 0.05 0.34 Na22_7.9cm_detB Na-22 1274 7.9cm 4215.35 [1270:1280] 7.70 +/- 0 0.18 Na22_8.1cm_detB Na-22 511 8.1cm 7541.784 [504:516] 24.88 +/- 0.06 0.33 Na22_8.1cm_detB Na-22 1274 8.1cm 4215.35 [1270:1280] 7.11 +/- 0 0.17