Use of the small proportional counter for carbon 14 measurement in 10 milligram carbon samples

Conference · Thu Jan 01 04:00:00 EST 1981

OSTI ID:6647623

Sayre, E V; Harbottle, G; Stoenner, R W; Otlet, R L

Ten years ago, the measurement of C-14/C-12 ratios in 10 milligram carbon samples seemed to be technically out of reach. However, two developments that make this goal possible have recently occurred: the first is an entirely new mass-spectrometric separation of C-14 and C-12 ions and their subsequent estimation by counting, while the second is simply the extension of conventional proportional counter operation (using CO/sub 2/ as counter gas) to very small size carbon samples. The first method is very fast, precise, and capable of treating samples of even sub-milligram size, but requires an expensive installation. The second method is slow (counting times of two months or more are necessary), can probably be made sufficiently precise to handle most problems, works down to sample sizes of 10 mg carbon, and is relatively inexpensive, especially to install in already existing radiocarbon laboratories. It is this second method and its implications that are discussed in the present paper.

• Research Organization: Brookhaven National Lab., Upton, NY (USA); UKAEA Atomic Energy Research Establishment, Harwell
• DOE Contract Number: AC02-76CH00016
• OSTI ID: 6647623
• Report Number(s): BNL-28506; CONF-810409-1
• Country of Publication: United States
• Language: English

Related Subjects

440300* -- Miscellaneous Instruments-- (-1989)
47 OTHER INSTRUMENTATION
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CARBON
CARBON 14
CARBON ISOTOPES
ELEMENTS
EVEN-EVEN NUCLEI
ISOTOPES
LIGHT NUCLEI
MEASURING INSTRUMENTS
MEASURING METHODS
NONMETALS
NUCLEI
PERFORMANCE
PROPORTIONAL COUNTERS
RADIATION DETECTORS
RADIOISOTOPES
SAMPLING
YEARS LIVING RADIOISOTOPES