Effect of helium on the Raman spectrum of methane in the range 2500-3300 cm-
A.S. Tanichev1, D.V. Petrov1,2, I.I. Matrosov1, K.K. Sharybkina1
1Institute of Monitoring of Climatic and Ecological Systems of the Siberian Branch of the Russian Academy of Sciences, Tomsk, Russia
2National Research Tomsk State University, Tomsk, Russia
Keywords: methane, helium, Raman spectroscopy, gas analysis
Abstract
The peak positions and half-widths of the Q -branch of the n1 band, as well as the ratios of intensities of the Q -branches of n3 and 2n2 bands of methane in a methane-helium mixture are measured at various pressures and concentrations. An empirical model has been developed for estimation of the helium concentration in a methane-bearing medium by measuring these spectral parameters. The error in the He concentration is found to be less than 1% when using the n1 band half-width. The ways of developing this technique and increasing its accuracy are considered.
|
