FORMATION AND QUENCHING OF POSITRONIUM IN GASES. II. RESULTS OBTAINED WITH THE POSITRON LIFETIME METHOD.
Abstract
The positron lifetime method has been used to study orthopositronium formation and quenching in argon, nitrogen, oxygen and mixtures of these gases. Quenching rates were found to be proportional to pressure for all gases and gas mixtures, except commerical grade argon. Highly quenched orthopositronium lifetimes were observed in pure argon and the formation fraction of positronium was estimated as 0.40 = 0.04. The quenching rate in oxygen was found to be (2.3 = 0.3) x 10 to the 7th power l/sec. atm. This rate holds for oxygen concentration greater than 2% in oxygen-argon mixtures. A constant quenching rate (250,000 = 5,000) 1/sec. atm was obtained for lower oxygen concentrations; this rate is not significantly different from the quenching rate (242,000 = 7,000) 1/sec. atm obtained for nitrogen-argon mixtures containing less than 10% nitrogen. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 09, 1963
- Accession Number
- AD0619609
Entities
People
- G. J. Celitans
- J. H. Green
- S. J. Tao
Organizations
- University of New South Wales