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A Fabry-Perot interferometer in a Ramsay mount is used in tandem with an echelle Hilger monochromator with pinholes instead of slits. The instrument, URSIES, is enclosed within a pressure chamber filled with Freon. Photoelectric pulse counting techniques and pressure scanning are used to record the spectrum. This design has four basic advantages: (1) The resolution of the scanner is variable from 5.0 A to 0.005 A, and the effective wavelength range is quite broad, from 3500 A to 13,000 A. (2) A light gain of ten over conventional grating scanners at resolutions of 0.1 A or better is achieved. (3) Very low levels of light from outside the wavelength passband reach the detector; for a resolution of 0.03 A at 6000 A this level is 5%. (4) There are very low levels of scattered light from the pinholes when extended sources are observed. The scattered light from the instrument at the edge of the solar disk is found to be less than 1% from 4000 A to 11,000 A. Measurements demonstrating these advantages are discussed.

A general systematic method to characterize the material composition of an object to be interrogated is posed and discussed. It employs neutrons to provide for the excitation of the nuclear isomer states of the isotopes constituting the body. Observation of the characteristic energies of the gamma rays emitted during the prompt relaxation identifies the isotope species. The intensity of the gamma rays together with neutron cross section data allows for the determination of species abundance. Measurements using multiple detectors that are spatially offset allows for the generation of images of the body composition isotope by isotope. This isomer excitation technique enables isotope identification for species of Z >= 3. Observation of neutron capture (gamma) emission supplements the method for hydrogen and helium-3. Several applications of the technique are described.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Spectrophotometric maps of Jupiter were made between 24 and 27 (UT) November 1974 on the McMath Solar Telescope at Kitt Peak National Observatory. We report a comparison between observed scaled reflectivities of the Jovian North Tropical Zone and the North Equatorial Belt at System II longitudes between 195 and 205 degrees. The belt/zone reflectivity ratios between 430 and 740 nm are related to the optical transmission curves of the organic and/or sulfur polymers synthesized by Khare and Sagan in a simulated Jovian atmosphere.

CN radical red system molecular constants, considering degenerate perturbation effects in shifts between electronic states

Umbral line profiles of Hα, Na D2 and Hei 10830 have been observed photoelectrically with a pressure scanning spectrometer, URSIES (Ultravariable Resolution Single Interferometer Echelle Scanner). Intermittent pulse counting techniques are applied with integration times as short as 0.8 s which permits selection of moments of good seeing and guiding even in poor climates. The Hα line profile shows in a medium-sized spot (A u = 100 × 10–6 SH) a pronounced weakening in the wings but a persistence of the line core in agreement with the results of Fricke and Elsasser (1965). The profile of the Hei 10830 line shows an unexpected strengthening over the umbra of the two spots which have been observed. The strengthening of the line in the umbral spectrum of a third spot has been confirmed by Dr. Mallia at the Oxford Solar Station (Gornergrat, Switzerland). Na D2 line profile together with continuum observations at λ4260, λ5890, and λ6530 have been accounted for with an empirical (T, τ) relation by one of us (Yun, 1971). The wavelength dependence and the absolute values from 4000 A to 14000 A of the intensity curve generated by this relation shows very good agreement with the intensities observed by Wohl et al. (1970) in a spot of similar diameter. Precision observations of the continuum at λ5890 indicate umbra-to-disk continuum ratios that are higher (0.104) than the Mercury calibrated value by Mattig (0.086) even when a maximal correction for scattered light is applied. Only Zwaan's (1965) cool umbral model atmosphere approaches Mattig's continuum value, but this model renders the absorption wings in Na D2 much too deep. It is suggested that future definitive observations should be carried out with coronagraphs under coronal skies or in satellites.

Solar rotational line positions due to red band in IR continuum region to resolve blue-violet ambiguity

The line-to-continuum intensity ratio for the center of the Na D2 absorption line in a spot of area 20 × 10−6 in the Rome Group 5847 was found to be 0.033±0.05 on 6–7/7/70 by two methods.

A new and optically very simple Michelson Fourier Transform Spectrometer has been developed. The development includes full consideration of the data processing problems and their solutions. The raw data are recorded on analog tape at the telescope, but digitization and all succeeding reductions are performed by digital computers. All the necessary data reduction software is complete, and we demonstrate that they produce spectra whose resolution compares favorably to the 5- and 16-A/mm Coude spectra in the Hiltner and Williams Stellar Spectral Atlas. The first results from this spectrometer have been published as "An Atlas of Stellar Spectra," Volumes I and II, whose wavelength coverage is between 0.4 and 1.0 pm. The atlas is available in digital tape format from the National Space Science Data Center, NASA-Goddard Space Flight Center, Greenbelt, Maryland 20771.© (1979) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Publisher Summary This chapter focuses on infra-red spectroscopy of cool stars with special attention to the instrumentation being used. A detailed discussion of the astronomical results of the studies mentioned appears where such results are more appropriate. The Carnegie Image Tube Committee began its infra-red investigations using small electrostatically focused tubes having thin mica windows with internal phosphor screens. These tubes had certain severe limitations when applied to spectroscopy, but the major problem was the limitation of the region of good focus due to the curved cathode and bowed mica window. The tube used is a 3 in. diameter cylinder 3 in. long whose actual cathode-to-mica distance is 2 in. The cathode is cooled to dry ice temperatures by a cold box, and both tube and cold box are carried within a 4.5-in. cylinder. Finally, one looks forwarded to the new discoveries, such as, spectral lines from previously un-observed elements or molecules that always follow the opening of new fields. A typical mica window using converter spectrogram is shown in this chapter.

Three properties of M stars are compared: (1) /3.5/ - /11/ colors, (2) two measures of 2.3-micron band absorption, and (3) two measures of 1.9-micron band absorption. We find that the 2.3-micron bands of 21 M giants and supergiants correlate with /3.5/ - /11/ colors at better than 99 per cent confidence. A comparable relation exists between the mean 1.9-micron bands and /3.5/ - /11/ colors of 23 M giants and Miras. The sum of the 1.9-micron + 2.3-micron band intensities correlates with /3.5/ - /11/ color at better than the 99.8 per cent level for 31 M stars. These relations are consistent with both CO and H2O cooling of M star boundaries. Binaries and Ia supergiants appear to depart from these relations.

N stars Y CVn, RY Dra and 19 Psc IR synthetic cyanide radical spectrum analysis, determining C 12/C 13 ratio

Rotational lines of the (0, 0) and (1, 1) bands of the C2(-) ion are shown to be coincident with absorption features in the CH star HD 201626 (C1, 1). Of the 72 lines of the (0, 0) band studied, the coincidences are within 0.04 A in all but two cases. These two lines are obviously blends, but of unknown origin. The identification of C2(-) must still be considered uncertain because the spectrum of HD 201626 is complex and many of the coincident lines are blended.