Engineering topics

Killinger, D. K.

Publications and source records attributed to Killinger, D. K..

21 records · Page 2

NASA NTRS1977

Simultaneous determination of rotational and translational temperatures of OH/2 Pi/ in a gas discharge

A simultaneous determination of the rotational and translational temperatures of OH(2 Pi) in a water-vapor discharge is reported. These temperatures were determined by measuring the strength and line shape of the absorption lines in the 2 Pi (v = 0) - 2 Sigma(+) (v = 0) transitions of OH using a CW tunable laser. It was found that the rotational distribution was thermalized, but the corresponding rotational temperature was much lower than the translational temperature. Possible implications of these results are discussed.

Wang, C. C.↗

NASA NTRS1977

Pulsewidth dependence of ozone interference in the laser fluorescence measurement of OH in the atmosphere

By varying the pulsewidth of the output from two dye lasers, it is verified experimentally that the steady-state interference level of OH due to laser-induced dissociation of ozone decreases linearly with decreasing pulsewidth of the exciting radiation. At low pressures, further reduction in the interference level due to the transient nature of OH formation processes was also observed. These results should greatly facilitate measurements of OH concentrations in the atmosphere.

Hanabusa, M.↗

NASA NTRS1976

Intensity and pressure dependence of resonance fluorescence of OH induced by a tunable UV laser

The intensity and pressure dependence of the fluorescence spectrum of OH in the presence of N2 and H2O molecules was studied. Saturation of the absorption transition was observed at low pressures, and the corresponding fluorescence signal was found to vary as the square root of the exciting intensity. This observed dependence agreed with the predicted dependence which took into account the presence of laser modes in the spectrum of the exciting radiation. With full laser power incident, a saturation parameter as high as 3 x 10 to the 5th was observed. The fluorescence spectrum was found to peak at 3145 and at 3090 A, with the relative peak intensities dependent upon gas pressures and upon the particular rotational electronic transition used for excitation. It is concluded that vibrational relaxation of the electronically excited OH due to water vapor in the system plays a dominant role in determining the observed fluorescence spectrum.

Killinger, D. K.↗