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Updated: Jun 10, 2026

Non-equilibrium Microwave Plasma for Efficient High Temperature Chemistry
Published on: August 1, 2017
Spectroscopy of methane using a Nd:YAG laser at 1.34 microm
Abstract:
We present measurements of the absorption coefficient of methane in the v(2) + 2v(3) band obtained with a neodymium:yttrium aluminum garnet (Nd:YAG) laser tuned by the use of an intracavity étalon to 7472 cm(-1) (1.3383 microm). The linewidth of the laser was shown to be comparable to that of the pressure-broadened methane feature while the absorption coefficient of methane at 1-atm pressure was measured to be 0.59 m(-1) atm(-1). These basic findings indicate that a practical methane detection system using laser radar (lidar) based on a Nd:YAG laser may be possible.
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