Proportional Counting Technique for Radiocarbon Measurements

Journal Article · Mon Jan 01 04:00:00 EST 1962 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.1717767· OSTI ID:4732064

Nydal, Reidar

A proportional counting system for radiocarbon dating is described in this article. The CO₂ counter has an effective volume of 1.2 liters and operates at a pressure of 2 atm. The total background is 1.10 counts/min and the standard net count on recent carbon is 16.0 counts/min. Maximum measurable age is 43,000 years. The end terminals of the courter have a few original details which serve to reduce inactive counter volume and the end effects. The ground capacity of the center wire has been reduced to a very small value (10 pf). Anticoincidence shielding is provided by a multiple-anode proportional counter. It is filled with C₃H₈ to a pressure of 1.3 atm and can operate continuously for at least one year without refilling. The counter walls of the ring counter and the CO₂ counter are connected together and supplied with the same high voltage. Shielding against gamma rays is provided by a 22-cm- thick iron shield around the counting unit and by a shell of 3.5-cm old lead between the CO₂ counter and the ring counter.

• Research Organization: Norwegian Inst. of Tech., Trondheim, Norway
• Sponsoring Organization: USDOE
• NSA Number: NSA-17-008631
• OSTI ID: 4732064
• Journal Information: Review of Scientific Instruments, Journal Name: Review of Scientific Instruments Journal Issue: 12 Vol. 33; ISSN 0034-6748; ISSN RSINAK
• Publisher: American Institute of Physics (AIP)
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
AGE ESTIMATION
ANODES
BACKGROUND
CARBON DIOXIDE
CARBON ISOTOPES
GAMMA RADIATION
PROPANE
PROPORTIONAL COUNTERS
RADIOISOTOPES
SHIELDING
WIRES