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Suenram, R. D.

Publications and source records attributed to Suenram, R. D..

7 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1990

Microwave spectra of van der Waals complexes of importance in planetary atmospheres

The Fourier-transform Fabry-Perot pulsed-molecular-beam microwave spectrometer at NIST was used to study the microwave spectra of a number of molecular dimers and trimers that may be present in planetary atmospheres. The weak van der Waals bonds associated with these species usually give rise to rotational-tunneling splittings in the microwave spectra. The microwave spectrum of the water dimer species was used to illustrate the complications that can arise in the study of the rotational spectra of these loosely bound species. In addition to the water dimer species, the microwave spectra of the following hydrogen-bonded and van der Waals complexes were studied: (CO2)2-H2O, CO2-(H2O)2, CO2-H2S, N2-H2O, CO-H2O, SO2-H2O, and O3-H2O.

Suenram, R. D.↗
NASA NTRS1983

Radio searches for additional interstellar molecules

Observations in the 2-mm wavelength range are reported which yield new interstellar molecular transitions of NH2CHO, SO2, H2CCO, U150820.5, and U150850.0 toward Sgr B2, and SO2, CH2CHCN, HCOOCH3, and U153513.0 toward Orion A. The first interstellar searches for HOCl, CH3CH2CCH, and CH3SiH3 were conducted, but these species were not detected. During these observations limits were also obtained on 2-mm wave transitions of N2O and NaOH toward several galactic sources of molecular emission.

Hollis, J. M.↗
NASA NTRS1983

An extensive galactic search for conformer II glycine

The most extensive galactic search reported to date for conformer II glycine, a higher energy form of the simplest amino acid has been conducted. The search utilized four glycine transitions at centimeter wavelengths and 21 at millimeter wavelengths to observe 18 galactic molecular sources and one comet. No conformer II glycine lines were detected, and measurements of representative sources were used to compute upper limits on total column densities. Several unidentified lines were detected and are reported here with some suggested possible identifications.

Snyder, L. E.↗
NASA NTRS1982

Detection of the torsionally excited state of methanol in Orion A

Torsionally excited methanol has been detected in Orion A, where three emission lines observed in the region of 93-100 GHz coincide with laboratory measurements of three methanol transitions. Torsionally excited methanol may therefore be used as a novel temperature probe, since this state lies near 200 per cm above the ground state, or about 290 K. No emission was detected from the transition arising from levels near 300 per cm, or approximately 430 K above the ground state.

Lovas, F. J.↗
NASA NTRS1981

New interstellar molecular transitions in the 2 millimeter range

A Sgr B2 kinetic temperature of about 47 K is derived based on observations of K components of the 9K-8K transition of CH3CCH. Interstellar line emission is detected in the 2 mm wavelength region from SO, (S-34)O, SO2, CH3OH, CH3CCH, CH3CH2CN, HC3N, and nine unidentified transitions. The methylacetylene K component data combined with the derived data reduction technique, demonstrates the utility of the molecule as a temperature probe of molecular clouds when two or more rotational transitions are observed. Evidence for the existence of interstellar HNO is presented, and an attempt is made to detect sulfuric acid, formic anhydride, and the 0-18 isotopic for CO2 in interstellar clouds and in the Venusian atmosphere during inferior conjunction.

Hollis, J. M.↗
NASA NTRS1980

A search for the lowest-energy conformer of interstellar glycine

The first search for the lowest-energy conformation of interstellar glycine has been carried out. An emission line has been detected in Sgr B2 which is coincident in frequency with the J(K-K+) = 14(1, 14)-13(1, 13) transition of conformer I glycine; while the carrier of the observed line is uncertain, no other frequency-coincident species are known, and hence glycine cannot be ruled out. Several previously unidentified lines have been identified as methyl formate. Evidence for the existence of the elusive interstellar ethylene oxide, the only reported interstellar ring-structure molecule, is discussed.

Hollis, J. M.↗