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.
COSINUS Measurements:




























Sample Description Manufacturer Mass (g) Live Time (days) Run Numbers Counting Dates
(if applicable)






















COSINUS G01 Cleaned with NuClean Only 7682.4 g 17.743 250529 May 29, 2025 Results:
238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co
Comments
Brass Plate



Jun 16, 2025 (mBq/kg) <0.036

<6.15

0.03 +- 0.24 1.19 +- 0.21 <1.56

<0.095

0.276 +- 0.056






(ppb or ppm) <2.916 ppt

<0.498 ppb

0.05 ppb +- 0.43 ppb 0.29 ppb +- 0.05 ppb <50.39 ppb
















Results: 210Pb:
7Be:

54Mn

228Ac:
58Co














(mBq/kg) <1828.00

1.20 +- 1.03 0.20 +- 0.07 0.54 +- 0.29 1.18 +- 0.13














(ppb or ppm) <148.07 ppb







0.13 ppb +- 0.07 ppb











COSINUS G02 Ultrasonically cleaned with NuClean 15364.8 g 21.806 250616 Jun 16, 2025 Results:
238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co
Comments
Brass Plate



Jul 8, 2025 (mBq/kg) <0.028

<2.76

<0.14

1.27 +- 0.16 0.56 +- 0.58 <0.13

0.32 +- 0.05






(ppb or ppm) <2.27 ppt

<0.22 ppb

<0.25 ppb

0.31 ppb +- 0.04 ppb 18.04 ppb +- 18.87 ppb














Results: 210Pb:
7Be:

54Mn

228Ac:
58Co














(mBq/kg) <4416.00

<0.77

0.18 +- 0.05 0.20 +- 0.24 0.88 +- 0.10














(ppb or ppm) <357.7 ppb







0.05 ppb +- 0.06 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:
210Po:














(mBq)





























(ppb or ppm)