Search NASA⌕ Search

Engineering topics

Lucht, R. A.

Publications and source records attributed to Lucht, R. A..

8 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1975

Temperature dependence of vibrational relaxation in the HF-DF, HF-CO2, and DF-CO2 systems. II

Measurements of vibrational energy transfer probabilities are presented for the temperature range 205-360 K for HF-DF, HF-CO2, and DF-CO2 gas mixtures. The present results provide an accurate determination of the inverse temperature dependence of the energy transfer probabilities exhibited by these systems. Large deactivation effects caused by HF (DF) polymers were observed for temperatures below 220 K.

Lucht, R. A.↗
NASA NTRS1974

Wavelength-selective, sequential Q-switching laser cavity

Single-frequency continuous output of laser is converted into series of high-power laser pulses at high repetition rates. Applications include pollutant detection by absorption, laser gain measurements at discrete wavelengths, laser propagation measurement, and laser plasma diagnostics.

Allario, F.↗
NASA NTRS1974

Temperature dependence of vibrational relaxation in the HF, DF, HF-CO2, and DF-CO2 systems

The laser excited fluorescence method has been employed to determine rate constants for V to V, R and V to R, T relaxation HF (nu = 1) and DF(nu = 1) by CO2 over the temperature range from 295 to 670 K. The self-deactivation rates for HF(nu = 1) and DF(nu = 1) by ground state molecules and the rate of V to V, R transfer from HF(nu = 1) and DF(nu = 1) to the CO2 (00/0/1) state exhibit a marked decrease with increasing temperature. The results provide additional evidence for the conversion of the large vibrational energy defects of the present systems into rotational motion of the hydrogen halide under the influence of a sizable attractive intermolecular potential well.

Lucht, R. A.↗
NASA NTRS1972

Simple technique for sequential Q-switching of molecular lasers.

A simple technique for sequentially Q-switching molecular lasers is discussed in which an optical scanner is used as an optical folding element in a laser cavity consisting of a stationary diffraction grating and partially reflecting mirror. Sequential Q-switching of a conventional CO2 laser is demonstrated in which over sixty-two transitions between 9.2 and 10.8 microns are observed. Rapid repetition rates (200 Hz) and narrow laser pulses (less than 5 microsec) allow conventional signal processing techniques to be used with this multiwavelength laser source which is a versatile tool for laser propagation studies, absorption spectroscopy, and gain measurements. Results of a preliminary experiment demonstrating the utility of measuring selective absorption of CO2 laser wavelengths by C2H4 are shown.

Lucht, R. A.↗
NASA NTRS1972

A technique for breaking ice in the path of a ship

A technique is described for breaking ice in the path of a ship. A laser is placed on the bow of the ship with apparatus to scan the ice in the path of the ship with the laser beam. The beam cuts or shatters the ice, enabling the ship to break the ice in its path.

Saunders, A. R.↗