Basic Standards and Calibrations

The gas counting system consists of six length-compensated internal-gas-proportional counters all within a 10 L vacuum tight chamber, shown here, enclosed in a pre-World War II steel cave. The system is used for the absolute calibration of gases such as ³H, ¹⁴C, ³⁷A, ³⁹A, ⁸⁵Kr, ¹²⁷X, ^131mXe, and ¹³³Xe.

Reference: Present Status in the Field of Internal Gas Counting. S.B. Garfinkel, W.B. Mann, F.J. Schima and M.P. Unterweger. First International Summer School on Radionuclide Metrology, Herceg-Novi, Yugoslavia, Sug 21-Sept.1, 1972. Nucl. Instr. Meth., 112,( No.1,2) 59 (1973).

Intercomparison of Internal Proportional Gas Counting of ⁸⁵Kr and ³H. J.L. Makepeace, F.E. Clark, J.L, Picolo, N. Coursol, E. Gunther, M.P. Unterweger. Nucl. Instr. Meth. Phys. Res. A 339, 343 (1994).

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Online: November 1997   -   Last update: March 1999