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Published on: March 22, 2019
Absorption measurement of nu2 + 2nu3 band of CH4 at 1.33 microm using an InGaAsP light emitting diode
1Tohoku University, Research Institute of Electrical Communication, Katahira 2-1-1, Sendai 980, Japan.
Abstract:
The combination band of nu2 + 2nu3 of CH4 at 1.33 microm (7512 cm(-1)) was observed at 0.3-cm(-1) resolution by a simple experimental arrangement using a near-infrared high-radiant InGaAsP light emitting diode (LED) and a Ge detector. Forty-six line centers were measured with accuracies of 0.03 cm(-1). The assignment of these manifolds was made by inspection of the P, Q, and R branches. The experimental result indicates that the nu2 + 2nu3 band can be used for fully optical remote monitoring of methane using InGaAsP optical sources in conjunction with an ultralow-loss optical fiber network.
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