Measurement of molecular electronic ground state oxygen O 2 (3Σ) in COIL device

Abstract

The improvement of the efficiency of singlet oxygen generators (SOG) in chemical oxygen iodine lasers (COIL) is still a key component for optimizing the performance of these lasers. Important parameters for the SOG operation are the utilization of chlorine and the singlet oxygen yield. In this work, the singlet oxygen yield is examined by two different methods: the absorption spectroscopy of ground state molecular oxygen O2(3Σ) based on a commercial diode laser system in conjunction with a multi-pass Herriott cell, and the measurement of spontaneous emission of the O2(3Σ)-O2(1Δ) transition in the near infrared (1.27 μm). A separate calibration cell has been build with geometry identical to the diagnostic duct of the DLR COIL for exact calibration of the absorption measurement. Results of simultaneously applied emission and absorption measurements are compared. This procedure allows the determination of the radiative lifetime of O2(1Δ) to a value of 3730 s.© (2005) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.