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.

RAMPS Measurements:

Sample Description

Manufacturer

Mass (g)

Live Time (days)

Run Numbers

Counting Dates
(if applicable)

RAMPS CW01

0.715 g

27.058

250620
250708
25070802

Jun 20, 2025

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

Silicon Carbide Crystal

Jul 8, 2025

(mBq/kg)

<71.40

<361.50

<15.08

19.59

54.72

2382.50

2104.00

<618.70

<114.80

(ppb or ppm)

<5.78 ppb

<29.28 ppb

<26.54 ppb

4.82 ppb

13.46 ppb

76.95 ppm

67.96 ppm

Results:

210Pb:

7Be:

54Mn:

228Ac:

(mBq/kg)

<3593.00

164.34

350.50

<86.80

45.60

92.95

(ppb or ppm)

<291.03 ppb

11.22 ppb

22.87 ppb

RAMPS CW02

1.7 g

3.879

260703
26070301

Jul 3, 2026

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

SiPM, ARRAY J-60035-4P-PCB

Jul 7, 2026

(mBq/kg)

12130.00

718.60

12470.00

1540.00

633.20

56.55

16690.00

1144.00

47858.00

9992.00

<290.00

153.90

330.30

(ppb or ppm)

982.53 ppb

58.21 ppb

1010.07 ppb

124.74 ppb

1114.43 ppb

99.53 ppb

4105.74 ppb

281.42 ppb

1545.81 ppm

322.74 ppm

Results:

210Pb:

7Be:

54Mn:

228Ac:

(mBq/kg)

10403.00

2643.00

<877.10

<239.00

14030.00

1037.00

(ppb or ppm)

842.64 ppb

214.08 ppb

3451.38 ppb

255.1 ppb

RAMPS CW03

Size: 6mm x 6mm

0.456 g

46.143

260707
260714
260724
260726

Jul 7, 2026

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

SiPM, Hamamatsu, S14160-6050HS

(x 4)

Aug 23, 2026

(mBq/kg)

2384.00

308.00

863.60

628.80

144.70

25.86

786.90

178.50

6249.80

4240.00

<929.30

<153.00

(ppb or ppm)

193.1 ppb

24.95 ppb

69.95 ppb

50.93 ppb

254.67 ppb

45.51 ppb

193.58 ppb

43.91 ppb

201.87 ppm

136.95 ppm

Results:

210Pb:

7Be:

54Mn:

228Ac:

(mBq/kg)

<3413.00

531.30

597.20

<173.10

683.90

272.50

(ppb or ppm)

<276.45 ppb

168.24 ppb

67.04 ppb

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:

57Co

58Co

(mBq/kg)

(ppb or ppm)