PAA Selenium

Using PAA ro measure Selenium concentrations.

According to Krouse<ref name="Krous1962"> H.R. Krause and H.G. Thode,"Thermodynamic Properties and Geochemistry of Iosotopic Compounds of Selenium",.Can. J. Chem., vol 40, pg 367</ref> , the fractional concentration of Se-82/Se-76 in plant material is observed to be less than from primordial (meteoric) concentrations by as much as 1.2%. Anaerobic bacteria are known to reduce selenates and senelites in biological systems. This may be the reason plant material has fractionation of selenium isotopes. They also observe excess concentrations of up to 0.4% in soil.

Plant material appears to detect environmental selenium.

Can one use plant material to measure the provenance of selenium?

Natural abundance of selenium

Isotope	Abundance
Se-74	0.86%
Se-76	9.23%
Se-77	7.60%
Se-78	23.69%
Se-80	49.80%
Se-82	8.82%

Possible reactions

Reaction	Half-life	Relative activity	Gamma-rays, keV (BR)
Se-74(gamma,n)Se-73	7.1 h	1.5E-1	361 (100)
Se-74(gamma,n)Se-73m	39 m	3.2	402 (4)
Se-74(gamma,np)As-72	26 h	1.0E-3	834 (100)
Se-76(gamma,n)Se-75	120 d	1.3E-2	265(29)
Se-77(gamma,p)As-76	26.4 h	4.4E-2	559(44)
Se-78(gamma,p)As-77	38.8 h	8.6E-2	239(2)
Se-80(gamma,n)Se-79m	3.9 m	5.9	96(10)
Se-80(gamma,np)As-78	1.5 h	2.2E-2	614(54)
Se-80(gamma,p)As-79	8.2 m	1.3	96(9)
Se-80(gamma,[math]a[/math]p)Ge-75	83 m	2.8E-1	265(11)

Can one perform PAA measurements of Se-82 and Se-76?

Neutron knockout of Se-82

If you knock a neutron out of Se-82 you produce the unstable isotope Se-81 which Beta emitts with half life of 18 min and a meta-state that emmits a 103 keV gamma with a 57 minute half life.

[math]{82 \atop 34\; }Se (\gamma,n){81 \atop \; }Se[/math]

Other prominent photons

260 & 276 keV for the 57 minute half life isotope

Neutron knockout of Se-76

If you knock a neutron out of Se-76 you produce the unstable isotope Se-75 which has a half life of 119 days.

[math]{76 \atop\; }Se (\gamma,n){75 \atop \; }Se[/math]

The prominent photons emitted have the following energies

136, 264, and 279 keV

The article below describes how plant material and soil contain Se-76 to Se-82 ratios that differ from other natural samples by 1.5%. They argue that it is due to the bacteria living in plant material.

File:Krouse CanJournChem 40 1962 p367.pdf

Plant material is a natural way to sample the selenium content to determine if there are difference isotopic ratios due to the impact of human activities on the environment.

Relative Yield Calculations

For this section, I am interested in finding the relative yield of Se-79 when compared to Se-81 and Se-75. Cross sections were found at this website: http://www-nds.indcentre.org.in/exfor/servlet/X4sSearch5?EntryID=220070

Below is a sample table of the cross section of a [math]{80 \atop 34\; }Se (\gamma,n){79 \atop \; }Se[/math] reaction occurring.

Energy (MeV)	Cross Section( millibarns)	**	Energy (MeV)	Cross Section (millibarns)	**	Energy (MeV)	Cross Section (millibarns)
10.02	7.1 +/- 0.2	**	15.02	110.9 +/- 4.6	**	20.02	83 +/- 5.7
10.22	10.3 +/- 0.4	**	15.22	118.9 +/- 4.1	**	20.22	79.9 +/- 6.2
10.42	12.9 +/- 0.5	**	15.42	125.8 +/- 5.5	**	20.42	67.1 +/- 7.2
10.62	16.2 +/- 0.5	**	15.62	132.9 +/- 4.5	**	20.62	70.9 +/- 6.6
10.82	19.2 +/- 0.6	**	15.82	132.7 +/- 5.9	**	20.82	72.2 +/- 7.6
11.02	22 +/- 0.6	**	16.02	127.6 +/- 5.6	**	21.02	66.8 +/- 6.5
11.22	23.8 +/- 1	**	16.22	132.4 +/- 5.3	**	21.22	69.7 +/- 7
11.42	28 +/- 1	**	16.42	130 +/- 7.6	**	21.42	68.2 +/- 8.4
11.62	28.6 +/- 1.2	**	16.62	125.4 +/- 6.2	**	21.62	68.6 +/- 7.4
11.82	30.4 +/- 1.5	**	16.82	137.4 +/- 6.7	**	21.82	60.9 +/- 7.3
12.02	33 +/- 1.4	**	17.02	138.1 +/- 7.5	**	22.02	58.5 +/- 7.3
12.22	34.9 +/- 1.8	**	17.22	130.4 +/- 8.3	**	22.22	56 +/- 7.8
12.42	37.6 +/- 1.4	**	17.42	114.9 +/- 6	**	22.42	69.7 +/- 7.7
12.62	41.5 +/- 2	**	17.62	110.8 +/- 6	**	22.62	60.1 +/- 8.8
12.82	43.6 +/- 2.5	**	17.82	104.4 +/- 7.4	**	22.82	60.9 +/- 8.7
13.02	46.7 +/- 2.8	**	18.02	108.7 +/- 6.6	**	23.02	58.8 +/- 9.3
13.22	51.9 +/- 2.6	**	18.22	102.4 +/- 7.3	**	23.22	50.6 +/- 9.7
13.42	56.7 +/- 1.5	**	18.42	104.3 +/- 5.7	**	23.42	31.5 +/- 8.7
13.62	61.4 +/- 2.9	**	18.62	104.1 +/- 5.5	**	23.62	37.7 +/- 8.7
13.82	69.5 +/- 3.3	**	18.82	91.1 +/- 7.8	**	23.82	29.5 +/- 10.2
14.02	78.7 +/- 4.4	**	19.02	90.5 +/- 5.5	**	24.02	32.4 +/- 8.6
14.22	84.9 +/- 3.6	**	19.22	85.7 +/- 6.2	**	24.22	32.8 +/- 9.6
14.42	93.3 +/- 2.7	**	19.42	91.4 +/- 6.6
14.62	100.5 +/- 4	**	19.62	84.9 +/- 5.6
14.82	105.1 +/- 4.6	**	19.82	90.3 +/- 8.1

Similar data can be found in the link above. Below is the plot for all the reactions of interest.

Below is a plot of 3 different isotopes of selenium with their cross sections as a function of energy.

Now to find the relative yields, I approximated the integral the above graph using a left hand Riemann sum with an interval width of 1 MeV and multiplied it by the natural abundance in the sample. Below is a table of the reactions and their integrated cross sections.

Reaction	Abundance	Integrated Cross Section (Mev * mb)
Se-82(gamma,n)Se-81	8.82%	1102.9
Se-80(gamma,n)Se-79	49.8%	1062.8
Se-76(gamma,n)Se-75	9.23%	836.5

Below are the equations for the relative yield of each isotope.

[math]{80 \atop 34\; }Se (\gamma,n){79 \atop \; }Se \frac {\lt math\gt {80 \atop 34\; }Se (\gamma,n){79 \atop \; }Se}[/math]

Experiments

Chlorine

It looks like Cl-35 is abundant as you see photon energies of 146 keV and 2127 keV (you can barely see 1176 keV) from Cl-34's decay (neutron knocked out of Cl-35).

The half life is 32 minutes.

Should check the half life from the run AccOnAlInDetASe-AinDetD_001.root using the calibration

MPA->Draw("0.18063+0.960133*evt.Chan>> SeRun_008(8000,0.5,8000.5)","evt.ADCid==3");

Irradiation of Horse Mineral Supplement

Below is the EMSL report for the horse feed sample. https://wiki.iac.isu.edu/index.php/File:EMSL_Report_Horse_Feed.pdf

Chlorine is a dominant signal

First, look at the peak around 146 keV

Next I plotted the counts as a function of time to get an exponentially decaying graph. When doing an exponential fit here, the parameter "b" given by root will be the decay constant.

Root gives a half life of 32.9508 +/- 0.01 minutes

Now do the same for the 2127 keV line

Here are the counts plotted as a function of time

Root gives a half life of 35.3962 +/- 0.2 minutes

Potassium is a potential signal

Looking at the spectrum for the fast irradiation sample, there are 2 prominent lines that could be from 38-K. The mechanism would be a single neutron knockout from a stable 39-K nucleus. The two most dominant energies of the three for 38-K are 2167 keV and 3936 keV and the half life is 7.63 minutes. Below is a fit to the energy spectrum histogram

Now check the half life

Root gives a half life of 8.03 +/- 0.02 minutes

Next check the 3936 peak

and check the half life

Root gives a value for b = - 1.14372x10^(-3), which in turn gives a half life of 10.1 minutes

It seems very possible that 38-K could be in the sample of horse feed.

First Observation of Se lines

Using the 44 Machine at 7 kW power and 44 meV incident electron energy to produce a bremsstrahlung spectrum with a mean energy of 15 meV.

All runs lasting less than 214 seconds have time stamp that gives real time if you divide by clock frequency of 20 MHz.  The first 32 bits are used for a real time measurement.

MDA and Se mass Calculations

To find the mass of the selenium in the irradiated horse feed sample, we need some masses and volumes of the horse feed. A vial containing 20mL of regular horse feed was massed. The mass of the vial was 13.6406g and the total mass of the vial and the horse feed was 31.8504g. This means the mass of the horse feed is 31.8504g - 13.6406g = 18.2098g. Since this mass is in a 20mL = 0.02L container, the density of the horse feed (assuming the mass difference between the non-irradiated and the irradiated horse feed is negligible) is 18.2098g/0.02L = 910.49 g/L. Now for the irradiated horse feed the mass of the container is 25.0259g and the total mass of the container and the sample is 43.7529g. The mass of the sample then is 43.7529g - 25.0259g = 18.727g. Now using the density found before we can find the volume of the irradiated horse feed within the container. density = 910.49g/L = 18.727/V. So V = (18.727g)/(910.49g/L) = 0.0206L. The EMSL report says that there are 0.56mg/L in the horse feed, so the mass of the selenium in the horse feed sample is 0.56mg/L*(0.0206L) = 0.011536mg.

Each of the calibration runs were used at position C in detector D. Below is the runlist for the isotopes used. The intervals used were (117:127) and (272:282) respectively.

Source	Serial #	Reference Date	Activity	Start	Stop	Live
Co-57	129735	07/01/08	1.074 micro Ci	16:17:37	16:27	601.10
Ba-133	129790	07/01/08	1.188 micro Ci	16:29:14	16:32	208.259

For the Co-57, the activity as of 09/07/16 is 0.0005 microCi and the intensity of the 122.3 keV line is 85.6%

= [math]\left (0.856 \right )\left ( 0.0005 \times 10^{-6} \mbox{Ci} \right) \left (\frac{ (3.7 \times 10^{10} \mbox{Hz}}{\mbox{Ci}} \right)= 15.84 Hz [/math] for the 122.3 line

For the Ba-133, the activity as of 09/07/16 is 0.69 microCi and the intensity of the 277.05 keV line is 7.164%

= [math]\left (0.07164 \right )\left ( 0.69 \times 10^{-6} \mbox{Ci} \right) \left (\frac{ (3.7 \times 10^{10} \mbox{Hz}}{\mbox{Ci}} \right)= 1828.97 Hz [/math] for the 277.05 line

Run	Source	Energy (keV)	Expected Rate (Hz)	HpGe Rate (Hz)	HpGe Det D Efficiency (%)
Eff_C_Co_57.root	Co-57	122.3	15.84	0.4526 - 0.2144	1.5
Eff_C_Ba_133.root	Ba-133	277.05	1828.97	20.58 - 0.07641	1.12

Now that the efficiency has been found, we must find the background rate to find the MDA. To find the background rate I used ROOT and plotted the energy spectra for Se_B_005 and HorseFeed_NoIrr. The windows of interest are the same as above. Each run's time was cut down to 1 hour.

First I will find the MDA for the window from (117:127). In Se_B_005, the activity was found to be 0.8433 HZ and in the HorseFeed_NoIrr the activity was found to be 0.2133 Hz, which gives a background rate of 0.63 Hz -> 37.6 cpm.

Now we can compute the MDA using this reference https://wiki.iac.isu.edu/index.php/File:Nwsltr-43re.pdf

I found the MDA to be [(2.71 + 4.65*(37.6 * 60)^1/2]/(60*0.015) = 249.1 dpm

Now I will find the MDA for the window from (272:282). In Se_B_005, the activity was found to be 0.7408 Hz and in HorseFeed_NoIrr the activity was found to be 0.08278. This means that the background activity is 0.66 Hz -> 39.48 cpm.

Now we can compute the MDA = [(2.71 + 4.65*(39.48 * 60)^1/2]/(60*0.012) = 318.1 dpm

Detector Efficiency

Below is the runlist for finding the efficiency of the detector at position R

Source	Serial #	Reference Date	Activity	Start	Stop	Live
Na-22	129743	7-01-08	9.427 microCi	15:49	16:19	1796.803
Cs-137	129793	7-01-08	1.006 microCi	14:25	14:56	1879.606
Mn-54	129807	7-01-08	11.77 microCi	15:00	15:30	1793.420
Co-60	129740	7-01-08	10.42 microCi	15:33	15:43	569.725

Below are the theoretical calculations for the theoretical decay frequencies

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

= [math]\left (0.99937 \right )\left ( 1.196 \times 10^{-6} \mbox{Ci} \right) \left (\frac{ (3.7 \times 10^{10} \mbox{Hz}}{\mbox{Ci}} \right)= 44,224 Hz [/math] for the 1274 line

= [math]\left (1.788 \right )\left ( 1.196 \times 10^{-6} \mbox{Ci} \right) \left (\frac{ (3.7 \times 10^{10} \mbox{Hz}}{\mbox{Ci}} \right)= 79122.6 Hz [/math] 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

= [math]\left (0.8521 \right )\left ( 0.891 \times 10^{-6} \mbox{Ci} \right) \left (\frac{ (3.7 \times 10^{10} \mbox{Hz}}{\mbox{Ci}} \right)= 28091.2 Hz [/math]

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

= [math]\left (0.99975 \right )\left ( 0.02328 \times 10^{-6} \mbox{Ci} \right) \left (\frac{ (3.7 \times 10^{10} \mbox{Hz}}{\mbox{Ci}} \right)= 861.1 Hz [/math] 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

= [math]\left (0.99 \right )\left ( 3.759 \times 10^{-6} \mbox{Ci} \right) \left (\frac{ (3.7 \times 10^{10} \mbox{Hz}}{\mbox{Ci}} \right)= 137692.17 Hz [/math] for the 1173 line

= [math]\left (0.999824 \right )\left ( 3.759 \times 10^{-6} \mbox{Ci} \right) \left (\frac{ (3.7 \times 10^{10} \mbox{Hz}}{\mbox{Ci}} \right)= 139058.52 Hz [/math] for the 1332 line

Below is a table where the actual efficiency will be calculated for position R (farthest position).

Run	Source	Energy (keV)	Expected Rate (Hz)	HpGe Rate (Hz)	HpGe Det D Efficiency (%)
Eff_003	Na-22	511	79122.6	(506:516) (4.309-0.065=4.244)	0.005
Eff_005	Cs-137	661.657	28091.2	(657:666)(1.105-0.02281=1.0821)	0.004
Eff_006	Mn-54	834.848	861.1	(830:839)(0.04037-0.009123=0.031247)	0.004
Eff_007	Co-60	1173.228	137692	(1164:1182)(3.686-0.01939=3.67)	0.003
Eff_003	Na-22	1274.537	44224	(1270:1279) (1.073-0.0057=1.0673)	0.002
Eff_007	Co-60	1332.492	139058.52	(1328:1337)(3.283-0.05702=3.22598)	0.002

Below is a runlist for position k

Source	Serial #	Reference Date	Activity	Start	Stop	Live
Na-22	129743	7-01-08	9.427 microCi	14:54	15:01	434.087
Cs-137	129793	7-01-08	1.006 microCi	15:48	15:55	413.925
Mn-54	129807	7-01-08	11.77 microCi	15:28	15:40	705.186
Co-60	129740	7-01-08	10.42 microCi	15:41	15:47	346.092

Below are the theoretical decay frequencies

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 April 14, 2016 =1.183micro Ci

= [math]\left (0.99937 \right )\left ( 1.183 \times 10^{-6} \mbox{Ci} \right) \left (\frac{ (3.7 \times 10^{10} \mbox{Hz}}{\mbox{Ci}} \right)= 43743.4 Hz [/math] for the 1274 line

= [math]\left (1.788 \right )\left ( 1.183 \times 10^{-6} \mbox{Ci} \right) \left (\frac{ (3.7 \times 10^{10} \mbox{Hz}}{\mbox{Ci}} \right)= 78262.5 Hz [/math] 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, April 14, 2016 activity =0.890 micro Ci expected rate for 661 line

= [math]\left (0.8521 \right )\left ( 0.890 \times 10^{-6} \mbox{Ci} \right) \left (\frac{ (3.7 \times 10^{10} \mbox{Hz}}{\mbox{Ci}} \right)= 28059.7 Hz [/math]

Mn-54, 11.77 on July 1, 2008, half life =312.20 +/- 0.07 days, 99.975% intensity on 834.826 , April 14, 2016 activity =0.02251micro Ci

= [math]\left (0.99975 \right )\left ( 0.02251 \times 10^{-6} \mbox{Ci} \right) \left (\frac{ (3.7 \times 10^{10} \mbox{Hz}}{\mbox{Ci}} \right)= 830.79 Hz [/math] 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, April 14, 2016 activity=3.74micro Ci

= [math]\left (0.99 \right )\left ( 3.74 \times 10^{-6} \mbox{Ci} \right) \left (\frac{ (3.7 \times 10^{10} \mbox{Hz}}{\mbox{Ci}} \right)= 136996.2 Hz [/math] for the 1173 line

= [math]\left (0.999824 \right )\left ( 3.74 \times 10^{-6} \mbox{Ci} \right) \left (\frac{ (3.7 \times 10^{10} \mbox{Hz}}{\mbox{Ci}} \right)= 138355.6 Hz [/math] for the 1332 line

Below are the actual efficiencies for position k

Run	Source	Energy (keV)	Expected Rate (Hz)	HpGe Rate (Hz)	HpGe Det D Efficiency (%)
Eff_k_002	Na-22	511	79122.6	(506:516)(49.21-0.6272=48.58)	0.06
Eff_k_006	Cs-137	661.657	28091.2	(657:666)(12.86-0.02281=12.837)	0.05
Eff_k_004	Mn-54	834.848	861.1	(830:839)(0.3204-0.009123=0.311)	0.04
Eff_k_005	Co-60	1173.228	137692	(1164:1182)(42.39-0.02053=42.369)	0.03
Eff_k_002	Na-22	1274.537	44224	(1270:1279) (12.53-0.005702)=12.52	0.03
Eff_k_005	Co-60	1332.492	139058.52	(1328:1337)(35.94-0.005072)	0.03

Below is a runlist for position C

Source	Serial #	Reference Date	Activity	Start	Stop	Live
Na-22	129742	7-01-08	1.146 microCi	12:55	12:57	129.782
Cs-137	129793	7-01-08	1.006 microCi	13:02	13:04	123.818
Mn-54	129806	7-01-08	1.226 microCi	13:11	13:21	613.754
Co-60	129739	7-01-08	1.082 microCi	13:08	13:09	103.599

Below are the calculations for the theoretical frequencies

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 May 5, 2016 =1.196micro Ci

= [math]\left (0.99937 \right )\left ( 0.14 \times 10^{-6} \mbox{Ci} \right) \left (\frac{ (3.7 \times 10^{10} \mbox{Hz}}{\mbox{Ci}} \right)= 5176.7 Hz [/math] for the 1274 line

= [math]\left (1.788 \right )\left ( 0.14 \times 10^{-6} \mbox{Ci} \right) \left (\frac{ (3.7 \times 10^{10} \mbox{Hz}}{\mbox{Ci}} \right)= 9261.8 Hz [/math] 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, May 5, 2016 activity = 0.89micro Ci expected rate for 661 line

= [math]\left (0.8521 \right )\left ( 0.891 \times 10^{-6} \mbox{Ci} \right) \left (\frac{ (3.7 \times 10^{10} \mbox{Hz}}{\mbox{Ci}} \right)= 28059.7 Hz [/math]

Mn-54, 1.226 microCi on July 1, 2008, half life =312.20 +/- 0.07 days, 99.975% intensity on 834.826 , May 5, 2016 activity =0.002micro Ci

= [math]\left (0.99975 \right )\left ( 0.002 \times 10^{-6} \mbox{Ci} \right) \left (\frac{ (3.7 \times 10^{10} \mbox{Hz}}{\mbox{Ci}} \right)= 73.98 Hz [/math] for the 834 line

Co-60, 1.082micro Ci July 1, 2008, half life 5.271 +/- 0.001 years, 99.0 % for 1173.237 and 99.9824 % for 1332.501, May 5, 2016 activity=0.39micro Ci

= [math]\left (0.99 \right )\left ( 0.39 \times 10^{-6} \mbox{Ci} \right) \left (\frac{ (3.7 \times 10^{10} \mbox{Hz}}{\mbox{Ci}} \right)= 14285.7 Hz [/math] for the 1173 line

= [math]\left (0.999824 \right )\left ( 0.39 \times 10^{-6} \mbox{Ci} \right) \left (\frac{ (3.7 \times 10^{10} \mbox{Hz}}{\mbox{Ci}} \right)= 14427.5 Hz [/math] for the 1332 line

Below is a table with the calculated efficiencies

Run	Source	Energy (keV)	Expected Rate (Hz)	HpGe Rate (Hz)	HpGe Det D Efficiency (%)
Eff_C_001	Na-22	511	9261.8	(506:516) (45.65-0.065=45.585)	0.5
Eff_C_002	Cs-137	661.657	28059.7	(657:666)(101.7-0.02281=101.67)	0.4
Eff_C_004	Mn-54	834.848	73.98	(830:839)(0.2704-0.009123=0.2612)	0.4
Eff_C_003	Co-60	1173	14285.7	(1164:1182)(34.24-0.01939=34.22)	0.2
Eff_C_001	Na-22	1274.537	5176.7	(1270:1279) (11.15-0.0057=11.14)	0.2
Eff_C_003	Co-60	1332.492	14427.5	(1328:1337)(28.05-0.05702=27.99)	0.2

Run List

Date	Time elapsed (Seconds)	Sample	Document Title	Start	Stop	Real	Live	Position
04-01-16	2.16x10^6	Se_B	Se_B_002	15:55	09:15	235989.882	235687.660	k
04-06-16	2.592x10^6	Se_B	Se_B_003	12:57	Interrupted	computer	crash	k
04-14-16	3.283x10^6	Se_B	Se_B_005	15:57	09:37	63581.784	63509.895	k
04-15-16	3.37x10^6	Sample D	Sample_D_001	14:47	08:23	236172.264	236173.271	k
04-19-16	3.715x10^6	Sample B	Sample_B_001	15:31	15:18	85634.862	85624.090	k
4-20-16	3.802x10^6	Sample C	Sample_C_001	15:22	10:19	68253.774	68232.238	k
04-21-16	3.888x10^6	Sample A	Sample_A_001	10:22	10:37	87292.409	87268.114	k
04-25-16	4.234x10^6	Sample E	Sample_E_001	11:36	10:03	80822.406	80795.679	k
04-26-16	4.32x10^6	Se_B	Se_B_008	10:06	10:29	87784.755	87664.070	k
05-05-16	5.098x10^6	Sample A	Sample_A_002	13:31	14:30	3605.507	3602.925	c
05-05-16	5.098x10^6	Sample B	Sample_B_002	14:34	15:26	3114.244	3112.620	c
05-05-16	5.098x10^6	Sample C	Sample_C_002	15:28	10:57	70124.788	70044.470	c
05-06-16	5.184x10^6	Sample D	Sample_D_002	10:59	15:34	16516.898	16512.570	c
05-06-16	5.184x10^6	Sample E	Sample_E_004	15:37	16:18	261654.225	261344.308	c
05-09-16	5.443x10^6	Se B	Se_B_012	16:20	11:08	67157.101	66660.298	c
05-10-16	5.5296x10^6	Sample A	Sample_A_004	11:03	15:19	15379.475	15363.017	c
05-10-16	5.5296x10^6	Sample B	Sample_B_004	15:22:04	11:43	73256.181	73220.324	c
05-16-16	6.048x10^6	Sample C	Sample_C_004	16:33	08:19	56758.980	56711.121	c
05-18-16	6.2208x10^6	Sample D	Sample_D_006	08:44:21	14:05	19271.829	19266.929	c
05-18-16	6.2208x10^6	Sample E	Sample_E_006	14:08	08:06	151108.258	150955.915	c
05-20-16	6.3936x10^6	Se_B	Se_B_014	08:08:47	08:44	261353.204	259621.655	c
05-23-16	6.6528x10^6	Sample A	Sample_A_006	08:48	13:49	18103.004	18091.523	c
05-23-16	6.6528x10^6	Sample B	Sample_B_006	13:52	13:24	84763.938	84696.083	c
05-24-16	6.7392x10^6	Sample C	Sample_C_006	13:28:28	10:28	75571.716	75502.871	c
05-31-16	7.344x10^6	Sample B	Sample_B_008	08:57:22	08:55	86282.861	86237.392	c
06-01-16	7.4304x10^6	Sample C	Sample_C_008	08:58:39	13:31	102739.504	102647.471	c
06-02-16	7.5168x10^6	Sample D	Sample_D_010	13:33	08:41	68915.044	68898.246	c

SeRun_01-11-16

SeRun_03-07-16

References

<references/>

File:Krouse CanJournChem 40 1962 p367.pdf

Goryachev, A. M., & Zalesnyy, G. N. (n.d.). The studying of the photoneutron reactions cross sections in the region of the giant dipole resonance in zinc, germanium, selenium, and strontium isotopes. Retrieved September 16, 2016, from http://www-nds.indcentre.org.in/exfor/servlet/X4sSearch5?EntryID=220070

MSDS

Selenium shot, amorphous, 2-6 mm, Puratronic, 99.999% Alfa Aesar product # 10603 File:AlphaAesarSelenium MDSD.pdf

Informative links

http://www.deq.idaho.gov/regional-offices-issues/pocatello/southeast-idaho-phosphate-mining/southeast-idaho-selenium-investigations/

https://inldigitallibrary.inl.gov/sti/3169894.pdf

http://giscenter.isu.edu/research/Techpg/sisp/index.htm

PAA_Research