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

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

DAMIC Measurements:

Sample Description

Manufacturer

Mass (g)

Live Time (days)

Counting Dates
(if applicable)

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

DAMIC 1

No. 20-20A,
Colour: white

1290.6 g

2.006

Nov 27, 2012

(mBq/kg)

12.31

5.95

11.05

187.29

<3.45

44.40

6.81

61837.83

3198.90

<3.17

0.24

6.84

Paint

Flame Control Coatings LLC, Niagara Falls, NY

Nov 29, 2012

(ppb or ppm)

1.00 ppb

0.48 ppb

0.90 ppb

15.17 ppb

<6.07 ppb

10.92 ppb

1.68 ppb

1997.36 ppm

103.32 ppm

DAMIC 2

CCD glued to wafer

18.5 g

5.967

Feb 7, 2013

(mBq/kg)

401.81

38.81

2300.03

589.06

190.70

31.21

203.47

25.90

<94.38

21.62

<8.21

CCD

Wafer is 1.06 mm thick, 63.6 mm wide, 80.1 mm high

Feb 13, 2013

(ppb or ppm)

32.55 ppb

3.14 ppb

186.30 ppb

47.71 ppb

335.64 ppb

54.93 ppb

50.05 ppb

6.37 ppb

<3.05 ppm

DAMIC 3

Ceramic is composed of aluminium nitride without silicon

94.4 g

2.708

Feb 4, 2013

(mBq/kg)

42.16

9.25

4109.85

530.95

333.96

30.06

32.10

8.61

45.55

66.74

<2.69

<0.80

7Be Signal:

Ceramic

Feb 7, 2013

(ppb or ppm)

3.42 ppb

0.75 ppb

332.90 ppb

43.01 ppb

587.77 ppb

52.91 ppb

7.90 ppb

2.12 pb

1471.29 ppb

2155.61 ppb

45.55 mBq/kg

39.20 mBq/kg

DAMIC 4

Bare CCD

2.1 g

6.740

Mar 11, 2012

(mBq/kg)

<32.99

0.00

4523.81

<63.70

<60.14

<282.00

47.62

95.24

<12.71

CCD

Mar 18, 2012

(ppb or ppm)

<2.67 ppb

0.00 ppb

366.43 ppb

<112.10 ppb

<14.79 ppb

<9.11 ppm

DAMIC 5

Lead bricks used for shielding DAMIC detector

8862.2 g

5.185

Sep 3, 2013

(mBq/kg)

<0.204

4.86

9.73

4.66

7.19

0.123

0.189

<0.35

<0.086

0.043

0.062

210Po:

Mini Lead Bricks

Sep 9, 2013

(ppb or ppm)

<0.016 ppb

0.39 ppb

0.79 ppb

8.21 ppb

12.65 ppb

0.030 ppb

0.047 ppb

<11.31 ppb

57.7 Bq/kg

17.5 Bq/kg

DAMIC 6

V2A Flex Circuit FNAL/CD/ESE

61.5 g

6.150

Jan 20, 2014

(mBq/kg)

4.80

5.69

84.55

188.62

0.73

7.98

1.64

6.14

227.64

87.81

<3.21

<2.14

Kapton Flex Cables

6 Cables

Jan 27, 2014

(ppb or ppm)

0.39 ppb

0.46 ppb

6.85 ppb

15.28 ppb

1.29 ppb

14.04 ppb

0.40 ppb

1.51 ppb

7.35 ppm

2.84 ppm

DAMIC 7

Epotek 301-2FL two-part epoxy

52.0 g

6.720

Jan 13, 2014

(mBq/kg)

<6.75

<105.21

5.23

5.68

9.90

6.83

<97.92

<7.40

<5.61

Epoxy

Epoxy Technology, Billerica, Mass, USA

Jan 20, 2014

(ppb or ppm)

<0.55 ppb

<8.52 ppb

9.20 ppb

9.99 ppb

2.43 ppb

1.68 ppb

<3.16 ppm

DAMIC 8

Mini lead bricks from U. of Zurich

10408.4 g

10.844

Sep 4, 2014

(mBq/kg)

<0.135

1.769

2.790

7.21

3.02

<0.075

<0.274

<0.129

<0.021

210Po:

Mini Lead Bricks

Sep 15, 2014

(ppt or ppb)

<10.96 ppt

0.14 ppb

0.23 ppb

12.68 ppb

5.31 ppb

<18.46 ppt

<8.87 ppb

16.03 Bq/kg

6.87 Bq/kg

DAMIC 9

Mini lead bricks from U. of Zurich

10379.0 g

13.895

Nov 12, 2014

(mBq/kg)

<0.148

<1.543

<1.98

0.037

0.106

0.01

0.74

<0.092

<0.013

210Po:

Etched Mini Lead Bricks

Same bricks at DAMIC 8, except that these bricks have been cleaned to remove surface contamination, the average thickness of lead removed was 24.5 microns.

Nov 26, 2014

(ppb or ppm)

<11.99 ppt

<124.95 ppt

<3.48 ppb

9.02 ppt

26.07 ppt

0.31 ppb

23.96 ppb

23.34 Bq/kg

6.41 Bq/kg

DAMIC 10

Ancient shipwreck lead

5324.8 g

10.573

Apr 23, 2015

(mBq/kg)

<0.26

<11.72

1.81

6.19

<0.61

<1.14

<0.71

<0.10

Pb Shielding Plate

May 4, 2015

(ppb or ppm)

<21.10 ppt

<0.95 ppb

3.18 ppb

10.90 ppb

<150.09 ppt

<133.71 ppb

Additional Activities:

(mBq/kg)

210Po:

<1.68 Bq/kg

124Sb:

3.60

0.47

110mAg:

0.49

0.21

(ppb or ppm)

Sample Description

Manufacturer

Mass (g)

Live Time (days)

Counting Dates
(if applicable)

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

DAMIC 11

Copper is Electropolished

6036.6 g

8.140

Apr 8, 2015

(mBq/kg)

<0.13

<4.00

<0.17

<0.12

<1.51

<0.071

<0.051

58Co Signal:

Cu Shielding Plates

There are 6 plates
At 97.5 mm x 100 mm x 12.5 mm or 8.2 mm (2 plates)

Apr 16, 2015

(ppb or ppm)

<10.88 ppt

<323.89 ppt

<291.58 ppt

<30.00 ppt

<48.77 ppb

0.191 mBq/kg

0.076 mBq/kg

DAMIC 12

Copper is Electropolished

182.8 g

6.888

Apr 16, 2015

(mBq/kg)

<2.61

<451.18

<9.44

<5.75

<39.79

<4.90

<1.72

58Co Signal:

Cu DAMIC Detector Frames

Apr 23, 2015

(ppb or ppm)

<211.36 ppt

<36.44 ppb

<16.62 ppb

<1.41 ppb

<1.29 ppm

0.00 mBq/kg

1.99 mBq/kg

DAMIC 13

Mini lead bricks from LPNHE Paris

11.872 kg

9.189

Apr 11, 2016

(mBq/kg)

<0.014

0.33

3.59

0.89

0.78

0.014

0.083

<0.99

<0.066

<0.0085

210Po:

Mini Lead Bricks

8 mini lead bricks

Apr 21, 2016

(ppb or ppm)

<1.11 ppt

0.03 ppb

0.29 ppb

1.56 ppb

1.37 ppb

3.52 ppt

20.33 ppt

<32.01 ppb

3.14 Bq/kg

4.66 Bq/kg

DAMIC 14

Sample contains:
Lockwasher #2 20.7 g
2/56 x 3/8 Capscrew 185.8 g

441.5 g

6.761

Apr 21, 2016

(mBq/kg)

<1.60

16.47

43.86

2.27

1.73

2.30

1.61

28.17

15.46

<1.76

0.76

0.57

Module Screws (Sample Prepared by Alvaro and karthik)

0/80 x 3/16 FSLMS BR 223.7 g
Lockwasher #0 12.3 g

Apr 28, 2016

(ppb or ppm)

<0.13 ppb

1.33 ppb

3.55 ppb

3.99 ppb

3.05 ppb

0.56 ppb

0.40 ppb

909.81 ppb

499.39 ppb

Additional Activities:

(mBq/kg)

228Ac:

<1.72

(ppb or ppm)

(Not in Equilibrium with other Th daughters)

<0.42 ppb

DAMIC 15

Sample Contains:
Lockwasher #4 13.5 g
SHCS #3/40 x 5/16 112.7 g

323.5 g

6.241

May 19, 2016

(mBq/kg)

1.08

1.70

68.88

64.38

<3.00

1.67

1.49

66.95

23.15

<0.98

<1.13

Box Screws (Sample Prepared by Alvaro and Karthik)

SHCS ¼-20-125” 110.0 g
+ insulator and ¼ washer
Hex nut ¼-20 58.4 g
Hex nut #6-32 27.2 g
Nylon Insulator #2 1.7 g

May 26, 2016

(ppb or ppm)

87.67 ppt

137.94 ppt

5.58 ppb

5.22 ppb

<5.28 ppb

0.41 ppb

0.37 ppb

2.16 ppm

0.75 ppm

In Progress and To Be Measured:

Sample Description

Manufacturer

Mass (g)

Live Time (days)

Counting Dates
(if applicable)

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

(mBq/kg)

(ppb or ppm)