AIR-BROADENED AND NITROGEN-BROADENED HALFWIDTH COEFFICIENTS AND PRESSURE SHIFTS IN THE $\nu_{3}$ BAND SPECTRAL REGION OF $^{12}CH_{4}$
Loading...
Date
1988
Journal Title
Journal ISSN
Volume Title
Publisher
Ohio State University
Abstract
A series of 26 high-resolution $(0.01 cm^{-1})$ room-temperature spectra of pure $CH_{4}^{+} CH_{4}$ in dry air and $CH_{4}$ in dry nitrogen was recorded in the $2700-3200 cm^{-1}$ spectral region with a signal-to-rms noise of 2000, using the Fourier transform spectrometer in the McMath telescope of the National Solar Observatory. Total pressures of 60 to 500 Torr were employed with absorption paths of 5 cm, 25 cm and 1.5 m and a mixing ratio of 0.01. The air-broadened and nitrogen-broadened halfwidths and the air and nitrogen pressure shifts have been measured by employing a nonlinear least-squares fitting technique. The unshifted line positions were determined from the spectra of pure $CH_{4}$ at low pressure. The experimentally determined values will be compared to previously reported values and values for corresponding transitions in other methane bands.
Description
Author Institution: Department of Physics, College of William and Mary; NASA Langley Research Center, Mail Stop 401A