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sample (source) | analysis | U conc. (ppb) |
Th conc. (ppb) |
K conc. (ppm) |
comments | |
by | method | |||||
Adhesives tested for MUNU St. Gotthard and NEMO |
GES | J. Busto et al., NIM
A 492 (2002) 35-42 [pdf from Science Direct] |
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Ag (powder) | E | GDMS | < 0.1 | < 0.1 | 0.5 | |
Al (commercial) | E | GDMS | 150(20) | 320(40) | ||
Al (high purity) | E | GDMS | 2 - 15 | 1 - 8 | ||
Al: Kryal UTH 0.2 (VAW) | S | NAA | < 0.043 | < 0.030 | ||
Al (low a) | E | GDMS | < 0.032 | < 0.023 | best < 3 ppt U, Th | |
Alumina (Coors Porcelain AD94: 94% purity) | F | GES | 420(6) 240(4) 720(10) |
440(10) 660(10) 30(2) |
from 214Pb (U), 228Ac
(Th); 214Bi 609 keV (U), 212Pb (Th); 214Bi 1764 keV (U), 208Tl (Th) |
|
Alumina (Coors Porcelain AD995: 99.5% purity) | F | GES | 56(3) 38(2) 83(5) |
160(10) 170(8) 7.4(12) |
from 214Pb (U), 228Ac
(Th); 214Bi 609 keV (U), 212Pb (Th); 214Bi 1764 keV (U), 208Tl (Th) |
|
Alumina (Westgo Al-300: 99.5% purity) | F | GES | 69(2) 51(2) 99(4) |
130(6) 170(6) 7.8(9) |
from 214Pb (U), 228Ac
(Th); 214Bi 609 keV (U), 212Pb (Th); 214Bi 1764 keV (U), 208Tl (Th) |
|
Alumina ceramic (R & W Products 909: 99.5% purity) | F | GES | 12(2) 35(3) 9(2) |
41(7) 37(5) - |
7.5(16) |
from 214Pb (U), 228Ac
(Th); 214Bi 609 keV (U), 212Pb (Th); 214Bi 1764 keV (U), 208Tl (Th) |
Alumina ceramic (R & W Products: previous, unfired) | F | GES | 8.3(10) 9.9(10) |
86(7) 33(3) |
5.4(10) |
from 214Pb (U), 228Ac
(Th); 214Bi 609 keV (U), 212Pb (Th) |
Alumina ceramic constituents: (a) Al2O3 | F | GES | 7.5(6) 13(1) 14(1) |
53(3) 20(2) - |
< 13 |
from 214Pb (U), 228Ac
(Th); 214Bi 609 keV (U), 212Pb (Th); 214Bi 1764 keV (U), 208Tl (Th) |
(b) MgO | F | GES | 31(8) 38(8) 60(20) |
< 270 100(20) - |
< 330 |
from 214Pb (U), 228Ac
(Th); 214Bi 609 keV (U), 212Pb (Th); 214Bi 1764 keV (U), 208Tl (Th) |
(c) SiO2 | F | GES | 47(6) 93(7) 160(16) |
700(40) 300(20) 49(6) |
31(5) |
from 214Pb (U), 228Ac
(Th); 214Bi 609 keV (U), 212Pb (Th); 214Bi 1764 keV (U), 208Tl (Th) |
(d) SiO2 (repeat of (c) with larger sample) | F | GES | 30(2) 27(2) 37(4) |
170(10) 180(10) 12(2) |
25(2) |
from 214Pb (U), 228Ac
(Th); 214Bi 609 keV (U), 212Pb (Th); 214Bi 1764 keV (U), 208Tl (Th) |
Cu (high purity) | E | GDMS | < 0.008 | < 0.006 | ||
Cu (low a) | E | GDMS | < 0.004 | < 0.003 | ||
GaP | E | GDMS | < 0.2 | < 0.2 | 0.008 | Rb < 0.3 ppb |
In | E | GDMS | < 0.03 | < 0.03 | < 0.001 | Rb < 0.05 ppb |
Mineral oil | K | TIMS | < 10-3 | < 10-3 | ||
NaI(Tl) (Harshaw; polyscin) | ? | ? | < 1 | < 1 | < 0.3 | |
Pb (`Doe Run') | J | a-count | 0.8 cph cm-2 | |||
Pb (JM low a) | J | a-count | 0.01 cph cm-2 | |||
Pb (low a) | E | GDMS | < 0.016 | < 0.014 | ||
Pb (Missouri) | E | GDMS | < 0.011 | < 0.010 | ||
Pb (modern) | J | a-count | 1 - 10 cph cm-2 | |||
Pb (40 year old) | J | a-count | 4.4 cph cm-2 | |||
Pb (50 year old) | J | a-count | 1.2 cph cm-2 | |||
Pb (125 year old) | J | a-count | 0.07 cph cm-2 | |||
Pb (440 year old, Spanish) | J | a-count | 0.03 cph cm-2 | |||
Quartz (Mark Optics Ge-124, natural) | F | GES | 18(1) 14.9(4) 31(1) |
11(1) 2.6(3) - |
< 9 |
from 214Pb (U), 228Ac
(Th); 214Bi 609 keV (U), 212Pb (Th); 214Bi 1764 keV (U), 208Tl (Th) |
Sapphire (Union Carbide; Czochralski grown) | F | GES | 1.0(2) < 6.1 |
< 6.6 0.5(2) |
< 8 |
from 214Pb (U), 228Ac
(Th); 214Bi 1764 keV (U), 212Pb (Th) |
Si | E | GDMS | < 3 | < 2 | < 0.01 | Rb < 5 ppb |
Si | E | GDMS | 0.1 | 0.1 | - | Rb 5 ppb |
Silica (Heraeus-Amersil `Suprasil II') | F | GES | < 2.4 5.7(8) - |
1.6(9) < 9 2.8(7) |
< 27 |
from 214Pb (U), 228Ac
(Th); 214Bi 609 keV (U), 212Pb (Th); 214Bi 1764 keV (U), 208Tl (Th) |
Water (`city') (after resin column) |
K | TIMS | 0.194 8.5×10-4 |
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Water (Kamioka) (treated) |
K | TIMS | 0.62 0.016 |
recirculating system now < 1 ppt | ||
ZnTe | E | GDMS | < 0.08 | < 0.07 | 0.004 | Rb < 0.2 ppb |
Notes:
NaI(Tl) data relates to ELEGANTS material (see Ejeri); `... U and Th contaminations are checked to be less than 1 ppb.', but no details of how; nor is it clear whether these checks refer to the NaI(Tl) or merely its Al can.
The Charles Evans data are from Ward, the JM from Ritala, and the VAW from Heusser.
I have converted the Fong et al. data from dpm kg-1 on the basis of U, Th chains in equilibrium; errors are my crude estimates of counting errors based on a stated absolute efficiency of 12% (at 835 keV; I have not attempted to correct this for actual g energies). Note, however, that Fong et al. describe the two SiO2 samples (alumina ceramic constituent) as `self-consistent within the statistics of counting.' Lines used are: 239 keV (212Pb), 352 keV (214Pb), 583 keV (208Tl), 911 keV (228Ac), and the two 214Bi lines.
Other remarks: