Alkaline Earth-Noble Gas Excimers.
Abstract
This project was undertaken to investigate the interaction between alkaline earth atoms in the triplet state and noble gas atoms. A major effort was devoted to producing large triplet state populations via laser excitation of the singlet state and collisional transfer to the triplet state. Cross sections for this process were measured using a new technique developed in this laboratory. These cross sections were much larger than expected, probably due to molecular curve crossings with intermediate states. The results predicted a population inversion in strontium was possible and an attempt was made to produce a strontium laser. Because of low laser pump power, an inversion of only fifty percent was achieved where as lasing threshold required ninety percent. Attempts to observe far wing emission from calcium and strontium interactions with noble gases at high temperatures failed because of the thermal energies involved and because of blackbody radiation. A technique was developed to do laser spectroscopy at low temperatures in a sealed cell containing metal atom vapors and high pressure noble gases. The technique was tested by measuring, for the first time, the excited state potential of the sodium-helium excimer molecule. This difficult experiment was made possible by state-of-the art laser spectroscopy and the low temperature technique, which enhanced the excimer emission by orders of magnitude. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 31, 1981
- Accession Number
- ADA108506
Entities
People
- John J. Wright
Organizations
- University of New Hampshire