Optika Atmosfery i Okeana Journal

Vol. 4, issue 05, article # 8

Bakarev A. E., Bondarchuk E. N., Razvalyaev V. N., Sinyukov A. M. Opto-acoustic detection of low concentrations of CH₃OH, CH₃CN, and SO₂. // Atmospheric and oceanic optics. 1991. V. 4. No. 05. P. 497–500. PDF
Copy the reference to clipboard

Abstract:

The design of an opto–acoustic detector (OAD) with a Helmholtz cavity is described. Data on the OAD frequency and phase parameters measured at a pressure of 0.5 Torr for pure CH₃OH for the lasing line of a CO₂ laser 9P(16) and the steepness of the Volt––Watt characteristic for pure CH₃OH and CH₃OH rarefied with air are presented. The limitting sensitivity and minimum detectable concentration of the spectrophone are estimated. The following data have been obtained: Cmin= 2.9E10^-6for CH₃OH for the lasing line of the CO₂ laser 9P(16), and Cmin= 5.8E10^-4 for SO₂ for the lasing line of the CO₂ laser 9R(18). Some measurements of the collisional broadening of the absorption lines of the CH₃OH , CH₃CN , and SO₂ molecules are presented. These values are (14 ± 2)MHz/Torr, (17±3)MHz/Torr, and (12 ± 2)MHz/Torr, respectively.