Durability of spectral lamps with vapors 87Rb for optically pumped frequency standards

The electrodeless spectral lamps with vapors of ⁸⁷Rb in many respects determine the accuracy and service life of optically pumped frequency standards. The service life of frequency standards should be 7-15 years with instability of intensity of light source within required limits during the specified period. Changes in ⁸⁷ Rb and buffer gas quantity, stability of radiation intensity and reproducibility of characteristics of spectral lamps are investigated. The object of research are lamps with a diameter up to 13 mm, filled with vapors of ⁸⁷Rb and buffer gas. The dependence of change of buffer gas pressure with time from discharge power, as well as speed of ⁸⁷Rb absorption by glass wall is investigated. A technique of accelerated checking of lamps durability and appropriate equipment, enabling one to predict the service life of lamps with high accuracy, are developed