Direct detection of singlet oxygen O2(a1 Δg)by absorption at the a1 Δg →b1 Σg+ transitionusing intracavity laser spectroscopy

Abstract

The absorption spectrum of singlet oxygen O2(a1 Δg)is detected in a gas phase at the a1 Δg →b1 Σg+ transition bythe method of intracavity laser spectroscopy using a broad-band Co : MgF2 laser emitting 200-μs pulses at a wavelength1.91 μm. In the case of Doppler broadening of absorptionlines at room temperature, the sensitivity of detection of O2(a1 Δg) is ~ (2 — 5) × 1014 cm-3 . It is shown that the gas temperature can be calculated from the dependence of absorptioncross sections for individual lines on the rotational quantumnumber.