Thermometry in a Gas Discharge Cell of an Optical Wavelength Calibrator

Resumo

Temperature and pressure in a sealed Ar cell of an optical wavelength calibrator are measured using diode laser spectroscopy. The values of the thermodynamic parameters allowed determination of the fluctuations of the shift of the argon line at 811.5 nm. The expected fluctuation amplitude appears lower than ±15 MHz. The result obtained indicates the applicability of the studied calibrator as an optical reference and the correctness of previous measurements of pressure shift coefficients of the 811.5 nm argon line.