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.

LEGEND 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

LEGEND CW01

Taiwan Semiconductor Manufacturing Company Limited

0.57 g

7.093

250425

Apr 25, 2024

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

ASIC Chips

J/N A16-07-374-4

(mBq/kg)

<132.50

<359.80

29.65

26.03

<163.00

7703.20

6561.00

<643.10

<263.30

Cold ATA V1

Die Size: 7.85 mm x 7.85 mm x 0.3 mm

(ppb or ppm)

<10.73 ppb

<29.14 ppb

52.18 ppb

45.81 ppb

<40.1 ppb

248.81 ppm

211.92 ppm

Results:

210Pb:

7Be:

54Mn:

228Ac:

Number of Units: 13

(mBq/kg)

<5312.00

<623.50

<210.40

<424.30

(ppb or ppm)

<430.27 ppb

<104.38 ppb

LEGEND CW02

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)

In Progress and To Be Measured:

Sample Description

Manufacturer

Mass (g)

Live Time (days)

Run Numbers

Counting Dates
(if applicable)

Comments

LEGEND CW01

Taiwan Semiconductor Manufacturing Company Limited

0.57 g

Results:

238U from 226Ra

238U from 234Th

235U

232Th

40K

137Cs

60Co

Comments

ASIC Chips

J/N A16-07-374-4

(mBq/kg)

Cold ATA V1

Die Size: 7.85 mm x 7.85 mm x 0.3 mm

(ppb or ppm)

Err:502

0 ppb

Err:502

Results:

210Pb:

7Be:

54Mn:

228Ac:

Number of Units: 13

(mBq/kg)

(ppb or ppm)

0 ppb

Err:502

LEGEND CW02

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)

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)