Title :
Performance of SAO model VLG-12 advanced hydrogen masers
Author :
Mattison, Edward M. ; Vessot, Robert F.C.
Author_Institution :
Smithsonian Astrophys. Obs., Cambridge, MA, USA
Abstract :
The performance of two VLG-12 masers that have operated at the US Naval Observatory is described. The effectiveness of the single-state selection system and of the storage bulb coatings is discussed. Among other results, it is shown that the masers´ initial frequency drift rates of several parts in 1015 per day decreased by factors of 2 to 4 over a period of 200 days
Keywords :
frequency measurement; hydrogen neutral atoms; masers; measurement standards; US Naval Observatory; VLG-12 masers; frequency drift rates; frequency measurement standard; single-state selection; storage bulb coatings; Atomic beams; Atomic measurements; Digital control; Frequency synthesizers; Hydrogen; Masers; Observatories; Seals; Vacuum systems; Vacuum technology;
Conference_Titel :
Frequency Control, 1990., Proceedings of the 44th Annual Symposium on
Conference_Location :
Baltimore, MD
DOI :
10.1109/FREQ.1990.177481
