Some Useful Information Concerning the results:

The Conversion factors for the primordial nuclides are given by:

1 Bq 238U/kg = 81 ppb U (81 x 10-9 gU/g)

The 238U decay chain gammas used are:

226Ra: 186.1 keV

214Pb: 295.21 and 351.92 keV

214Bi: 609.31, 1120.29, 1764.49 and 2204.21 keV

The relationships are valid for any daughters in the 238U, 235U or 232Th chain only if the chain is in equilibrium.

1 Bq 232Th/kg = 246 ppb Th (246 x 10-9 gTh/g)

The 232Th decay chain gammas used are:

212Pb: 238.63 and 300.09 keV

208Tl: 583.19 and 2614.53 keV,

228Ac: 911.21 keV

1 Bq 40K/kg = 32300 ppb K (32300 x 10-6 gK/g)

The 40K decay chain gamma used is:

40K: 1460.83 keV

1 Bq 235U/kg = 1.76 ppm U (1.76 x 10-6 gU/g)

The 235U decay chain gammas used are:

235U: 143.76, 163.33 and 205.31 keV

Background Measurements of the Vue des Alpes Detector

Sample Description

Manufacturer

Mass (g)

Live Time (days)

Run Numbers

Counting Dates
(if applicable)

Background 1

Efficiency assumes no samples

36.187

171213
171218

Dec 13, 2017

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

Completely Empty Detector

Jan 19, 2018

(mBq)

1.87

0.17

5.04

1.61

0.061

0.052

1.35

0.17

15.26

1.93

0.201

0.096

0.063

0.054

Results:

210Pb:

7Be:

54Mn:

228Ac:

(mBq)

76.66

14.04

<0.67

<0.081

0.88

0.26

Background 2

Efficiency assumes no samples

17.497

180212

Feb 12, 2018

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

Completely Empty Detector

Mar 2, 2018

(mBq)

1.32

0.22

3.73

2.32

0.233

0.076

0.79

0.22

18.39

2.84

0.392

0.159

0.024

0.082

Results:

210Pb:

7Be:

54Mn:

228Ac:

(mBq)

101.72

20.73

<0.98

<0.12

1.03

0.37

Background 3

Efficiency assumes no samples

51.750

180319
180417

Mar 18, 2018

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

Completely Empty Detector

May 12, 2018

(mBq)

2.23

0.15

4.95

1.39

0.140

0.046

1.274

0.133

17.11

1.74

0.433

0.090

<0.068

Results:

210Pb:

7Be:

54Mn:

228Ac:

(mBq)

101.15

12.63

0.50

0.55

0.075

0.065

1.21

0.22

Background 4

Efficiency assumes no samples

82.542

180522
18053001
180801

May 22, 2018

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

Completely Empty Detector

Aug 12, 2018

(mBq)

2.05

0.12

6.24

1.17

0.124

0.034

1.328

0.114

15.52

1.39

0.319

0.067

0.122

0.037

Results:

210Pb:

7Be:

54Mn:

228Ac:

(mBq)

79.59

9.88

0.73

0.46

0.040

0.047

1.13

0.18

Background 5

Efficiency assumes no samples

76.532

190910
190914
190915

Sep 10, 2019

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

Completely Empty Detector

Nov 28, 2019

(mBq)

2.04

0.12

6.37

1.19

0.133

0.035

1.164

0.116

16.22

1.45

0.385

0.076

0.097

0.039

Results:

210Pb:

7Be:

54Mn:

228Ac:

(mBq)

82.07

10.15

0.48

0.44

<0.052

1.48

0.19

Background 6

Efficiency assumes no samples

55.304

200324
200430

Mar 24, 2020

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

Completely Empty Detector

May 19, 2020

(mBq)

3.40

0.18

7.80

1.57

0.154

0.043

2.40

0.17

29.09

2.38

0.25

0.09

0.032

0.050

Results:

210Pb:

7Be:

54Mn:

228Ac:

(mBq)

191.42

21.95

0.49

0.55

0.043

0.060

2.09

0.26

Background 7

Efficiency assumes no samples

7.257

210111
210119

Jan 11, 2021

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

Completely Empty Detector

Jan 20, 2021

(mBq)

2.06

0.38

8.57

3.77

0.22

0.11

1.14

0.37

29.32

5.23

0.36

0.23

<0.12

Results:

210Pb:

7Be:

54Mn:

228Ac:

(mBq)

172.52

44.42

<1.55

<0.21

1.73

0.60

Combined Background

Combined Backgrounds of Runs 1+2+3+4+5

238.322

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

Completely Empty Detector

Efficiency assumes no samples

(mBq)

2.414

0.094

6.61

0.85

0.333

0.060

1.534

0.082

18.65

1.22

0.405

0.052

0.151

0.026

Results:

210Pb:

7Be:

54Mn:

228Ac:

(mBq)

99.20

7.71

0.32

0.33

0.006

0.034

1.394

0.041

Completed Sample Measurements Counted on the Vue des Alpes Detector

The measurements of the samples below take into account the background measurement shown above. If a measurement is below the background then the upper bound shown is the 90% confidence limit.

PICO Measurements:

Sample Description

Manufacturer

Mass (g)

Live Time (days)

Run Numbers

Counting Dates
(if applicable)

PICO V01

Model No. S1328PD3T72
Omega

60.1 g

15.659

200825

Aug 25, 2020

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

White RTD Wire Leads

Sep 10, 2020

(mBq/kg)

5.38

7.22

<127.80

2.54

2.40

<9.16

69.28

72.04

<5.89

<1.78

(ppb or ppm)

0.44 ppb

0.58 ppb

<10.35 ppb

4.47 ppb

4.22 ppb

<2.25 ppb

2237.78 ppb

2326.89 ppb

Results:

210Pb:

7Be:

54Mn:

228Ac:

(mBq/kg)

140700.00

38520.00

<53.17

<1.90

<14.98

(ppb or ppm)

11.4 ppm

3.12 ppm

<3.69 ppb

PICO V02

Model No. S1328PD3T72 Omega

23.9 g

11.639

200910

Sep 10, 2020

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

Red RTD Wire Leads

Sep 22, 2020

(mBq/kg)

4.67

20.77

<422.90

6.19

6.59

<27.98

74.99

232.80

<17.53

<3.64

(ppb or ppm)

0.38 ppb

1.68 ppb

<34.25 ppb

10.89 ppb

11.59 ppb

<6.88 ppb

2.42 ppm

7.52 ppm

Results:

210Pb:

7Be:

54Mn:

228Ac:

(mBq/kg)

148160.00

69770.00

132.14

84.27

<14.75

<42.97

(ppb or ppm)

12 ppm

5.65 ppm

<10.57 ppb

PICO V03

Hard Copper Wire

45.2 g

13.687

200922

Sep 22, 2020

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

PICO Heater Cables

Oct 6, 2020

(mBq/kg)

<13.25

<127.70

<3.89

6.70

9.82

<148.60

9.17

6.88

<5.33

(ppb or ppm)

<1.07 ppb

<10.34 ppb

<6.85 ppb

1.65 ppb

2.42 ppb

<4.8 ppm

Results:

210Pb:

7Be:

54Mn:

228Ac:

58Co

57Co

(mBq/kg)

143110.00

62600.00

3.33

41.87

2.55

4.67

21.23

16.07

0.54

3.65

7.05

6.27

(ppb or ppm)

11.59 ppm

5.07 ppm

5.22 ppb

3.95 ppb

PICO V04

Preamps for Piezos for the PICO and SBC experiments

21.2 g

25.610

210421
210429

Apr 21, 2021

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

Kapton Preamp Boards

Quantity: 28

May 17, 2021

(mBq/kg)

1504.00

45.52

4544.00

459.10

89.11

7.12

2226.00

71.56

4239.80

321.90

<9.34

<5.98

(ppb or ppm)

121.82 ppb

3.69 ppb

368.06 ppb

37.19 ppb

156.83 ppb

12.53 ppb

547.6 ppb

17.6 ppb

136.95 ppm

10.4 ppm

Results:

210Pb:

7Be:

54Mn:

228Ac:

(mBq/kg)

259030.00

88590.00

<108.00

12.60

9.45

2254.00

80.58

(ppb or ppm)

20.98 ppm

7.18 ppm

554.48 ppb

19.82 ppb

PICO V05

BLU-25751706 Lot 230328
3/32 “ x 7”

276.2 g

5.088

231026
23102601
231028
231029

Oct 26, 2023

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

Tungsten Ceriated Welding Electrodes

Air Liquide, Blueshield, Made in China

231030

Oct 31, 2023

(mBq/kg)

<186.40

9577.00

4406.00

<193.20

570400.00

13220.00

14541.00

902.70

61.79

71.90

<50.83

Sample contains 20 electrodes

(ppb or ppm)

<15.1 ppb

775.74 ppb

356.89 ppb

<340.03 ppb

140.32 ppm

3.25 ppm

469.67 ppm

29.16 ppm

Results:

210Pb:

7Be:

54Mn:

228Ac:

(mBq/kg)

<2.62E6

2903.00

633.10

2985.60

182.10

207300.00

4975.00

(ppb or ppm)

<212.22 ppm

51 ppm

1.22 ppm

PICO V06

BLU-25751706 Lot 220713
3/32 “ x 7”

422.2 g

4.687

231031 23103101 231101 231102 231103

Oct 31, 2023

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

Tungsten Ceriated Welding Electrodes

Air Liquide, Blueshield, Made in China

Nov 5, 2023

(mBq/kg)

<68.47

927.80

1908.00

64.68

53.28

93870.00

2196.00

7938.60

475.80

<66.87

<10.82

Sample contains 30 electrodes

(ppb or ppm)

<5.55 ppb

75.15 ppb

154.55 ppb

113.84 ppb

93.77 ppb

23.09 ppm

0.54 ppm

256.42 ppm

15.37 ppm

Results:

210Pb:

7Be:

54Mn:

228Ac:

(mBq/kg)

2324000.00

2368000.00

1866.60

317.70

1527.00

84.04

105300.00

2557.00

(ppb or ppm)

188.24 ppm

191.81 ppm

25.9 ppm

0.63 ppm

PICO V07

BLU-25751708 Lot 230204
1/8 “ x 7”

251.5 g

3.126

231105

Nov 5, 2023

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

Tungsten Ceriated Welding Electrodes

Air Liquide, Blueshield, Made in China

Nov 8, 2023

(mBq/kg)

<115.70

<7092.00

<235.50

577200.00

13410.00

16792.00

1114.00

<111.70

<59.50

Sample contains 10 electrodes

(ppb or ppm)

<9.37 ppb

<574.45 ppb

<414.48 ppb

141.99 ppm

3.3 ppm

542.38 ppm

35.98 ppm

Results:

210Pb:

7Be:

54Mn:

228Ac:

(mBq/kg)

<7.92E6

3190.90

949.60

3172.30

181.60

222400.00

5483.00

(ppb or ppm)

<641.52 ppm

54.71 ppm

1.35 ppm

PICO V08

BLU-25751708 Lot 230515
1/8 “ x 7”

1004.4 g

7.786

231108

Nov 8, 2023

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

Tungsten Ceriated Welding Electrodes

Air Liquide, Blueshield, Made in China

Nov 16, 2023

(mBq/kg)

<33.37

263.40

2273.00

299.50

113.60

599300.00

14060.00

17403.00

929.60

<59.25

<14.68

Sample contains 40 electrodes

(ppb or ppm)

<2.7 ppb

21.34 ppb

184.11 ppb

527.12 ppb

199.94 ppb

147.43 ppm

3.46 ppm

562.12 ppm

30.03 ppm

Results:

210Pb:

7Be:

54Mn:

228Ac:

(mBq/kg)

<1.79E7

3007.20

395.00

2659.20

146.10

213800.00

5309.00

(ppb or ppm)

<1449.9 ppm

52.59 ppm

1.31 ppm

PICO V09

Molex wire ring connectors

100.6 g

8.757

240305
240313

Mar 5, 2024

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

Wire Ring connectors

Types: 16-14 MX
22-18 MX

Mar 15, 2024

(mBq/kg)

<4.41

99.35

249.00

<4.27

<5.03

<64.56

<3.73

<3.75

(ppb or ppm)

<357.21 ppt

8.05 ppb

20.17 ppb

<7.52 ppb

<1.24 ppb

<2.09 ppm

Results:

210Pb:

7Be:

54Mn:

228Ac:

(mBq/kg)

371410.00

337700.00

46.92

30.78

7.53

3.97

<7.22

(ppb or ppm)

30.08 ppm

27.35 ppm

<1.78 ppb

In Progress Sample Measurements Counted on the Vue des Alpes Detector

In Progress and To Be Measured:

Sample Description

Manufacturer

Mass (g)

Live Time (days)

Run Numbers

Counting Dates
(if applicable)

Next Sample

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

(mBq/kg)

(ppb or ppm)

Results:

210Pb:

7Be:

54Mn:

228Ac:

(mBq/kg)

(ppb or ppm)