Ultra-low radioactivity flexible printed cables

EPJ Techniques and Instrumentation

Table 3 Measurements of the ²³⁸U, ²³²Th and ^natK concentrations in the final SiPM and CCD custom cables. Each row within the cable type lists the values for a given subsample (identified by the repetition number in the second column) with the uncertainties indicating the instrumental uncertainty. ^∗Averages are reported as the average and standard deviation of the central values of all replicates for that isotope (upper limits excluded). Where all replicates are upper limits, the largest upper limit is reported

Cable	Rep.	²³⁸U [pg/g]	²³²Th [pg/g]	^natK [ng/g]
SiPM Cable (Custom)	1	20 ± 2	<9.8	<38
	2	21 ± 2	<9.4	<37
	3	18 ± 2	<8.6	<34
	4	20.9 ± 1.2	<10.4	47 ± 6
	5	19 ± 2	<10.3	32 ± 8
	6	18.8 ± 1.2	<12.3	<20
	7	19.6 ± 1.5	<12.0	52 ± 7
	8	19 ± 3	<12.0	28 ± 7
	Avg.^∗	20 ± 2	<12.3	40 ± 12
CCD Cable (Custom)	1	32 ± 2	12 ± 3	559 ± 13
	2	31 ± 4	11 ± 3	529 ± 12
	3	29 ± 2	<8.9	572 ± 12
	4	32 ± 3	16 ± 4	569 ± 13
	5	31 ± 2	<11.7	558 ± 12
	6	30 ± 2	<10.9	546 ± 9
	7	30 ± 2	<11.1	515 ± 9
	Avg.^∗	31 ± 2	13 ± 3	550 ± 20