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UK DM project: radioactivity test results

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Individual items

sample (source) analysis U chain
g/day
Th chain
g/day
K
g/day
comments
by method
Capacitor (Homestake) W GES 95 - 1900(a) 50 - 1000(b) < 110 - 900  
Diode (Homestake) W GES < 30 - 60(a) 20(b) 460 - 610  
Electronics (EMI PMs) S GES? ~ 30 ~ 10 ~ 4  
Inductor (Homestake) W GES 950(a) 2100(b) 230  
Mu-metal (Bicron) S GES 1.4(2) 104(c) < 40(d) 1400(500) (for 3" PM)
Mu-metal (Homestake) W GES 3.2 104(a) < 210(b) 3300 (for 3" PM?)
O-ring (Homestake) W GES < 160 - 1600(a) < 320(b) < 300  
PM tube, 2" (EMI low b/g) S GES? 2.1(9) 104 1.8(5) 104 6800(1100) from components
PM tube, 2" (EMI low b/g) - - ~ 4000 ~ 2000 ~ 1000 92/93 goal
PM tube, 2" (EMI best UV) S GES? ~ 6 104 ~ 3 104 ~ 3 104  
PM tube, 3" (Bicron) S GES 2.3(2) 104(c) 5300(1500)(d) 1.46(5) 104  
PM tube, 3" (EMI low b/g) S GES? 6.5(9) 104 3.4(10) 104 1.1(2) 104  
PM tube, 3" (EMI low b/g) S GES? 30(12) 103 2.6(6) 104 1.0(1) 104 from components
PM tube, 3" (EMI low b/g) - - ~ 6000 ~ 3000 ~ 1500 92/93 goal
PM tube, 3" (EMI best UV) S GES? ~ 105 ~ 5 104 ~ 4 104  
PM tube (ET 9823B) S GES? 5.1(2) 105 2.43(8) 105 8.5(4) 104  
PM tube (ET9823QB) S GES? 4.4(3) 105 2.0(1) 105 3.5(3) 105 quartz window
PM tube, 3" (Homestake) W GES 5.1 104 - 1.05 105(a) 3.2 104 - 1.1 105(b) 3 104 - 3.8 105  
PM tube, 5" (EMI 9390 B53) S   3(2) 104 1.1(3) 104 8(2) 103  
PM tube, 5" (Hamamatsu R1512) S   ~ 105 ~ 2 104 ~ 105 `K-free'(!)
PM tube, 5" (Hamamatsu R1512) S   ~ 104 ~ 104 ~ 104 low b/g
PM tube, 8" (ET 9354B) S GES? 5(3) 104 2.3(7) 104 1.6(4) 104 low b/g
Resistor (Allen-Bradley) I NAA 6.5(5) 4.4(1) 0.86(3) without leads
Resistor (Homestake) W GES 32 - 950(a) 32 - 2100(b) < 50 - 1200  
Transistor (Homestake) W GES 32 - 63(a) 42(b) < 30 - 50  
Analysts: Analysis methods:
I: ICI Tracerco GES: Gamma Emission Spectroscopy
S: supplier's data NAA: Neutron Activation Analysis
W: N. A. Wogman et al.

Notes:

(a): from 214Bi g count, U chain assumed in equilibrium; 2.20 gs in chain.
(b): from 208Tl g count, Th chain assumed in equilibrium; 2.65 gs in chain.
(c): from 226Ra g count, U chain assumed in equilibrium; 2.20 gs in chain.
(d): from 228Ac g count, Th chain assumed in equilibrium; 2.65 gs in chain.

Other remarks:

ppm: parts per million by weight, = conc. 106 ppb: parts per (US) billion by weight, = conc. 109
ppt: parts per (US) trillion by weight, = conc. 1012   errors: 0.035(10) (e.g.) means 0.035 0.01 (1 s.)
1 kru = 103 decays/day/kg