References to Appendix II
Hess, V. F. and Vancour, R., Physical Review, 76, No. 8,
P, 1205 (Oct. 15, 1949).
Wilkinson, D. H., Ionization Chambers and Counters, Cambridge,
1950, P. 51 ff.
Actually the 0.84 rhm figure applies to a radium needle with 0.5 mm
platinum filtration.
The filtration of the platinum (0.2 mm) and
the aluminum holder (1.82 mm) combined is closely equivalent to a
filtration of 0.43 mm platinum.
In this connection, it is noted that
the dose output of radium in equilibrium with its daughter products
has recently been revised to 0.825 rhm/l mg Ra with 0.5 mm platinum
filtration (cf. National Bureau of Standards Technical News Bulletin,
41, 12, P. 198, Dec. 1957). Using this new figure and taking into
account the slightly smaller filtration of our source, our recalcu-
lated estimate for the dose rate output would be 0.83 rhm/1l mg Ra.
Ohmart, P. E., et al, The Radioelectric Effect, AEC Report MLM-629
(Nov. 1, 1951).
STAREE IE SO I ee ye