Measurements of OH Radicals in a Low-Power Atmospheric Inductively Coupled Plasma by Cavity Ringdown Spectroscopy

$29.00 plus tax (Refund Policy)

Buy Article:


Cavity ringdown spectroscopy is applied to line-of-sight measurements of OH radicals in an atmospheric-pressure argon inductively coupled plasma, operating at low power (200 W) and low gas flows (~18 liters/min). Density populations of the single S21(1) rotational line in the OH A 2σ+X 2Π (0–0) band are extracted from the measured line-of-sight absorbance. Plasma gas kinetic temperatures, derived from the recorded line shapes of the S21(1) line, ranged from 1858 to 2000 K with an average uncertainty of 10%. Assuming local thermodynamic equilibrium, an assumption supported by the comparison of the experimental and simulated spectra, the spatially averaged total OH number density at different observation heights was determined to be in the range of 1.7 × 1020–8.5 × 1020 (m-3) with the highest OH density in the plasma tail. This work demonstrates that ringdown spectra of the OH radical may be used both as a thermometer for high-temperature environments and as a diagnostic tool to probe the thermodynamic properties of plasmas.

Keywords: Cavity ringdown spectroscopy; Inductively coupled plasma; OH radical

Document Type: Research Article


Affiliations: 1: Diagnostic Instrumentation & Analysis Laboratory, Mississippi State University, 205 Research Blvd., Starkville, Mississippi 39759 2: epartment of Physics and Astronomy, University of Southern Mississippi, Box 5046, Hattiesburg,Mississippi 39406 3: Department of Physics and Engineering Physics, University of Tulsa, 600 South College Avenue,Tulsa, Oklahoma 74104

Publication date: June 1, 2004

More about this publication?
Related content



Share Content

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
Cookie Policy
ingentaconnect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more