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Classification and Identification of IRAS Sources with Low-Resolution Spectra
IRAS low-resolution spectra were extracted for 11,224 IRAS sources.These spectra were classified into astrophysical classes, based on thepresence of emission and absorption features and on the shape of thecontinuum. Counterparts of these IRAS sources in existing optical andinfrared catalogs are identified, and their optical spectral types arelisted if they are known. The correlations between thephotospheric/optical and circumstellar/infrared classification arediscussed.
| Irregular variables of type Lb. New JHKL'M-photometry for 160 stars.
This paper presents new near infrared observations of 160 Irregularvariables of type Lb in the JHKL'M filter bands. These measurements aresupplemented by data for additional 56 stars taken from the literature.In total 220 datasets are available because of some multipleobservations. From our sample, 216 stars have near infrared (NIR)photometry now. Our sample of visually bright Lb-variables displays verysimilar infrared properties when compared with SRa- and SRb-variables.Derived from NIR-two colour diagrams the oxygen-rich Lbs seem to haveintermediate atmospheric conditions between Miras and normal giants.There may be a sligthly larger "contamination" with non AGB-giants thanin the case of the semiregulars. Using only our IR-colours the S- andthe Carbon-stars among the Lbs again are undistinguishable fromSR-variables of the same chemistry.
| The Galactic Distribution of Aliphatic Hydrocarbons in the Diffuse Interstellar Medium
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1995ApJ...440..697S&db_key=AST
| Near-infrared absorption spectroscopy of interstellar hydrocarbon grains
We present new 3600 - 2700/cm (2.8 - 3.7 micrometer) spectra of objectswhose extinction is dominated by dust in the diffuse interstellarmedium. The observations presented here augment an ongoing study of theorganic component of the diffuse interstellar medium. These spectracontain a broad feature centered near 3300/cm (3.0 micrometers) and/or afeature with a more complex profile near 2950/cm (3.4 micrometers), thelatter of which is attributed to saturated aliphatic hydrocarbons ininterstellar grains and is the primary interest of this paper. As in ourearlier work, the similarity of the absorption bands near 2950/cm (3.4micrometers) along different lines of sight and the correlation of thesefeatures with interstellar extinction reveal that the carrier of thisband lies in the dust in the diffuse interstellar medium (DISM). Atleast 2.5% of the cosmic carbon in the local interstellar medium and 4%toward the Galactic center is tied up in the carrier of the 2950/cm (3.4micrometer) band. The spectral structure of the diffuse dust hydrocarbonC-H stretch absorption features is reasonably similar to UV photolyzedlaboratory ice residues and is quite similar to the carbonaceouscomponent of the Murchison meteorite. The similarity between the DISMand the meteoritic spectrum suggests that some of the interstellarmaterial originally incorporated into the solar nebula may have survivedrelatively untouched in primitive solar system bodies. Comparisons ofthe DISM spectrum to hydrogenated amorphous carbon and quenchedcarbonaceous composite are also presented. The AV/tau ratiofor the 2950/cm (3.4 micrometer) feature is lower toward the Galacticcenter than toward sources in the local solar neighborhood(approximately 150 for the Galactic center sources vs. approximately 250for the local ISM sources). A similar trend has been observed previouslyfor silicates in the diffuse medium by Roche & Aitken, suggestingthat (1) the silicate and carbonaceous materials in the DISM may bephysically correlated and (2) there is either dust compositionalvariation in the galaxy or galactic variation in the grain populationdensity distribution. We also note a possible absorption feature near3050/cm (3.28 micrometers), a wavelength position that is characteristicof polycyclic aromatic hydrocarbons (PAHs).
| Grain Mantles in the Taurus Dark Cloud
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1993MNRAS.263..749S&db_key=AST
| The SVS Numbering Series Discontinued
Not Available
| The Perkins catalog of revised MK types for the cooler stars
A catalog is presented listing the spectral types of the G, K, M, and Sstars that have been classified at the Perkins Observatory in therevised MK system. Extensive comparisons have been made to ensureconsistency between the MK spectral types of stars in the Northern andSouthern Hemispheres. Different classification spectrograms have beengradually improved in spite of some inherent limitations. In thecatalog, the full subclasses used are the following: G0, G5, G8, K0, K1,K2, K3, K4, K5, M0, M1, M2, M3, M4, M5, M6, M7, and M8. Theirregularities are the price paid for keeping the general scheme of theoriginal Henry Draper classification.
| IRAS catalogues and atlases - Atlas of low-resolution spectra
Plots of all 5425 spectra in the IRAS catalogue of low-resolutionspectra are presented. The catalogue contains the average spectra ofmost IRAS poiont sources with 12 micron flux densities above 10 Jy.
| Revised MK spectral types for G, K, and M stars
A catalog of spectral types of 552 G, K, and M stars is presented, whichis classified on the revised MK system. Stellar representatives of thehalo, disk, and arm populations in all parts of the sky are included.Photoelectric V magnitudes are given, as are intensity estimates of anyfeatures which make the spectrum appear peculiar as compared to thespectrum of a similar normal star. Abundance indices are also providedin the following lines or bands: CN, barium, Fe, calcium, and CH.
| The Distribution of the BD M-Type Stars Along the Galactic Equator.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1958ApJ...128..510N&db_key=AST
| The Distribution of Late M-Type Stars Along the Galactic Equator.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1956ApJ...124..522N&db_key=AST
| Spectral Classification of Red Variables Along the Galactic Equator.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1956ApJ...124..346C&db_key=AST
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Observation and Astrometry data
| Constellation: | Aquila |
| Right ascension: | 19h13m54.43s |
| Declination: | +02°37'30.8" |
| Apparent magnitude: | 8.963 |
| Proper motion RA: | 4.2 |
| Proper motion Dec: | -1.7 |
| B-T magnitude: | 10.874 |
| V-T magnitude: | 9.121 |
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