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Results for “INFRARED SPECTRA”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 145 records · Page 8
All sourcesNASA NTRSDOE OSTI
NASA NTRS1988

Theoretical infrared spectra of SN 1987A

A simple model for the ejecta of SN 1987A is used to show that the expected fluxes in infared fine structure lines from nickel, cobalt, iron, argon, sulfur, silicon, and neon are likely to be detectable for several years following the supernova explosion. Energy sources due to radioactive decay and a central pulsar are considered separately. Most of the mass of heavy elements resides in the inner, pure metal shells of the ejecta, so that the infrared lines will probe the temperature, ejecta masses, and dynamics of this region and not the overlying, hydrogen-rich envelope.

Colgan, Sean W. J.↗
NASA NTRS1999

ISO Mid-Infrared Spectra of Reflection Nebulae

Our goal is to test predictions of models attributing the IEFs to polycyclic aromatic hydrocarbons (PAHs). Interstellar models predict PAHs change from singly ionized to neutral as the UV intensity, Go, decreases.

reflection nebulae dust infrared astronomy↗
NASA NTRS2005

Infrared Spectroscopic Analyses of Sulfate, Nitrate, and Carbonate-bearing Atacama Desert Soils: Analogs for the Interpretation of Infrared Spectra from the Martian Surface

The Atacama Desert of northern Chile is the driest desert on Earth, receiving only a few mm of rain per decade. The Mars climate may, in the past, have been punctuated by short-lived episodes of aqueous activity. The paleo-Martian environment may have had aqueous conditions similar to the current conditions that exist in the Atacama, and Mars soils may have formed with soil chemistry and mineralogy similar to those found in the Atacama. Remote and in-situ analysis of the Martian surface using infrared technology has a long heritage. Future investigations of the subsurface mineralogy are likely to build upon this heritage, and will benefit from real life lessons to be learned from terrestrial analog studies. To that end, preliminary results from a near- and mid-infrared spectroscopic study of Atacama soil profiled at a range of depths are presented.

Dalton, J. B.↗
NASA NTRS1995

Mid-Infrared Spectra of Comets P/Borrelly, P/Faye, and P/Schaumasse

A 10 micrometer silicate emission feature has been discovered in the spectra of comets P/Borrelly and P/Faye at R of roughly 1.5 AU although this feature was not observed in P/Schaumasse. A model is presented to show how the shape of the silicate feature can depend on the way in which silicate and absorbing material are mixed in the grains.

comets↗
NASA NTRS1998

Infrared spectra of substituted polycylic aromatic hydrocarbons

Calculations are carried out using density functional theory (DFT) to determine the harmonic frequencies and intensities of 1-methylanthracene, 9-methylanthracene, 9-cyanoanthracene, 2-aminoanthracene, acridine, and their positive ions. The theoretical data are compared with matrix-isolation spectra for these species also reported in this work. The theoretical and experimental frequencies and relative intensities for the neutral species are in generally good agreement, whereas the positive ion spectra are only in qualitative agreement. Relative to anthracene, we find that substitution of a methyl or CN for a hydrogen does not significantly affect the spectrum other than to add the characteristic methyl C-H and C triple bond N stretches near 2900 and 2200 cm-1, respectively. However, addition of NH2 dramatically affects the spectrum of the neutral. Not only are the NH2 modes themselves strong, but this electron-withdrawing group induces sufficient partial charge on the ring to give the neutral molecule spectra characteristics of the anthracene cation. The sum of the absolute intensities is about four times larger for 2-aminoanthracene than those for 9-cyanoanthracene. Substituting nitrogen in the ring at the nine position (acridine) does not greatly alter the spectrum compared with anthracene.

NASA Discipline Exobiology↗
NASA NTRS1970

Infrared spectra for 32 stars

Stellar IR spectra for types A0 to M7, using Mertz type Michelson interferometer as Fourier transform spectrometer

Johnson, H. L.↗