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:

234Th: 63.29 and 92.59 keV
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: 277.371, 583.19, 860.557 and 2614.53 keV,

228Ac: 209.253, 338.320, 463,004, 911.21, 964.766 and 968.971 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

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

SBC Measurements:

Sample Description

Manufacturer

Mass (g)

Live Time (days)

Run Numbers

Counting Dates
(if applicable)

238U from 226Ra

238U from 234Th

235U

232Th

228Ac

137Cs

210Pb

40K

SBC CW01

SiPMs labelled 96 & 97

2.6 g

21.516

200302

Mar 2, 2020

(mBq/kg)

45060.00

2019.00

28170.00

2292.00

2328.00

72.40

10940.00

708.10

6009.00

568.30

222.88

593.60

20544.00

611.80

68019.00

49610.00

Hamamatsu VUV4 Quad SiPM (MEG-II Style)

(2 SiPMs)

Mar 24, 2020

(ppb or ppm)

3649.86 ppb

163.54 ppb

2281.77 ppb

185.65 ppb

4097.28 ppb

127.42 ppb

2691.24 ppb

174.19 ppb

1478.21 ppb

139.8 ppb

1664.06 ppb

49.56 ppb

2197.01 ppm

1602.4 ppm

(mBq / SiPM)

58.58

2.62

36.62

2.98

3.03

0.09

14.22

0.92

7.81

0.74

0.29

0.77

26.71

0.80

88.42

64.49

SBC CW02

PCB Size:
15 mm x 15 mm x 1.5 mm

21.2 g

15.552

200722

Jul 22, 2020

(mBq/kg)

8740.00

337.30

7803.00

615.60

498.80

14.69

15710

688.20

8831.00

349.00

<299.80

4824.20

324.50

PCBs for the SBC SiPMs

Quantity: 30

0.7 g/ PCB

Aug 11, 2020

(ppb or ppm)

707.94 ppb

27.32 ppb

632.04 ppb

49.86 ppb

877.89 ppb

25.85 ppb

3864.66 ppb

169.3 ppb

2172.43 ppb

85.85 ppb

390.76 ppb

26.28 ppb

Additional Activities:

(mBq/kg)

40K:

11541.00

11560.00

227Ac:

1233.00

92.76

54Mn:

212.23

493.20

60Co:

1005.00

678.20

(ppb or ppm)

372.77 ppm

373.39 ppm

2170.08 ppb

163.26 ppb

SBC CW03

Kester Lead-Free Solder

10.6 g

8.887

210623
210627
210630

Jun 23, 2021

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

Tin-Silver Solder

Solder: Sn 96.5%
Sg: 3.0%
Cu: 05%

Jul 2, 2021

(mBq/kg)

<7.54

528.20

364.40

5.07

5.36

<13.30

<329.40

<36.93

<7.49

Lot: W201038
Solder diameter: 0.8 mm

(ppb or ppm)

<0.61 ppb

42.78 ppb

29.52 ppb

8.92 ppb

9.43 ppb

<3.27 ppb

<10.64 ppm

Also counted as PGT SBC P09

Results:

210Pb:

7Be:

54Mn:

228Ac:

Kester
Itaska, IL, USA

(mBq/kg)

10329.00

7231.00

24.90

39.77

<7.34

<11.50

(ppb or ppm)

836.65 ppb

585.71 ppb

<2.83 ppb

SBC CW04

Stainless Steel

53.5 g

11.486

210505

May 5, 2021

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

Stainless Steel

Pressure Vessel Body

May 17, 2021

(mBq/kg)

1.45

1.43

<25.48

<0.31

<3.24

15.50

47.23

<11.46

<6.62

PV Drawing Item #3

(ppb or ppm)

0.12 ppb

<2.06 ppb

<0.55 ppb

<0.8 ppb

0.5 ppm

1.53 ppm

Also counted as VDA SBC-V01

Results:

210Pb:

7Be:

54Mn:

228Ac:

57Co

58Co

(mBq/kg)

838.27

907.90

<11.73

9.39

2.71

<3.67

0.74

0.73

<2.53

(ppb or ppm)

67.9 ppb

73.54 ppb

<0.9 ppb

SBC CW05

Units: 10

2.85 g

6.589

211029
211101
211102

Oct 29, 2021

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

Four-Pin RTD Connectors

Nov 5, 2021

(mBq/kg)

4972.00

196.50

9792.00

758.60

282.60

19.92

9605.00

372.00

12476.00

2337.00

<180.70

<135.20

(ppb or ppm)

402.73 ppb

15.92 ppb

793.15 ppb

61.45 ppb

497.38 ppb

35.06 ppb

2.36 ppm

0.09 ppm

402.97 ppm

75.49 ppm

Results:

210Pb:

7Be:

54Mn:

228Ac:

(mBq/kg)

4722.50

1342.00

<603.20

<174.10

8948.00

372.80

(ppb or ppm)

382.52 ppb

108.7 ppb

2.2 ppm

0.09 ppm

SBC CW06

Epoxy colour is blue

6.25 g

27.383

211105

Nov 5, 2021

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

Stycast Epoxy

Dec 3, 2021

(mBq/kg)

160.80

9.87

2658.00

163.00

48.19

2.45

119.80

9.49

473.77

225.00

<59.64

<14.21

(ppb or ppm)

13.02 ppb

0.8 ppb

215.3 ppb

13.2 ppb

84.81 ppb

4.32 ppb

29.47 ppb

2.33 ppb

15.3 ppm

7.27 ppm

Results:

210Pb:

7Be:

54Mn:

228Ac:

(mBq/kg)

<545.10

<65.98

<16.26

75.30

13.88

(ppb or ppm)

<44.15 ppb

18.52 ppb

3.41 ppb

SBC CW07

Kapton Insulated single conductor wire

8.45 g

13.587

211203
211207
211213

Dec 3, 2021

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

RTD Wire

Kapton, Silver plated copper

Dec 17, 2021

(mBq/kg)

<5.92

19.85

45.18

1.33

1.10

<7.68

1045.90

734.30

<527.90

<12.42

(ppb or ppm)

<0.48 ppb

1.61 ppb

3.66 ppb

2.34 ppb

1.93 ppb

<1.89 ppb

33.78 ppm

23.72 ppm

Results:

210Pb:

7Be:

54Mn:

228Ac:

(mBq/kg)

<660.40

553.13

570.40

<112.80

13.44

10.47

(ppb or ppm)

<53.49 ppb

3.31 ppb

2.58 ppb

SBC CW08

Circuit Board Material: Arlon 85N

1.85 g

27.571

211217
220103

Dec 17, 2021

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

PCB Materials

OnBoardCircuits Inc.

Jan 14, 2022

(mBq/kg)

8782.00

268.40

15040.00

924.10

506.90

18.63

12300.00

399.70

14881.00

1851.00

<164.10

<118.60

(ppb or ppm)

711.34 ppb

21.74 ppb

1218.24 ppb

74.85 ppb

892.14 ppb

32.79 ppb

3025.8 ppb

98.33 ppb

480.66 ppm

59.79 ppm

Results:

210Pb:

7Be:

54Mn:

228Ac:

(mBq/kg)

7378.00

1067.00

<454.80

177.64

78.80

14050.00

425.30

(ppb or ppm)

597.62 ppb

86.43 ppb

3456.3 ppb

104.62 ppb

SBC CW09

FBK VUV HD4 1x1cm

13.5 g

14.680

240125

Jan 25, 2024

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

SiPMs

Foundazione Bruno Kessler, Italy

Feb 9, 2024

(mBq/kg)

<2.03

<15.80

<1.24

<4.35

344.60

191.50

<31.10

<7.92

Quantity: 30

(ppb or ppm)

<0.16 ppb

<1.28 ppb

<2.18 ppb

<1.07 ppb

11.13 ppm

6.19 ppm

Results:

210Pb:

7Be:

54Mn:

228Ac:

(mBq/kg)

<263.40

<21.85

<8.89

<6.48

(ppb or ppm)

<21.34 ppb

<1.59 ppb

In Progress and To Be Measured:

Sample Description

Manufacturer

Mass (g)

Live Time (days)

Run Numbers

Counting Dates
(if applicable)

Comments

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)