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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.
| Semiregular variables of types SRa and SRb. New JHKL' M-photometry for 44 stars.
This paper supplements Kerschbaum & Hron (1994, Paper IIa), wherenew JHKL'M observations of 200 Semiregular variables (SRVs) of types SRaand SRb were presented with additional 44 near infrared observations and5 literature data sets. The total sample was defined in Kerschbaum &Hron (1992, Paper I) by means of a certain limit in bolometricmagnitude. From the sample of 350 objects, 303 now have near infrared(NIR) photometry. In total 339 datasets are available because of somemultiple observations. A detailed analysis of the whole dataset will bepresented in a forthcoming paper.
| Semiregular variables of types SRa and SRb. New JHKL'M-photometry for 200 stars.
This paper presents new JHKL'M observations of 200 Semiregular variables(SRVs) of types SRa and SRb. The sample was defined in Kerschbaum &Hron (1992a, Paper I) by means of a certain limit in bolometricalmagnitude. From the sample of 350 objects, 260 now have near infrared(NIR) photometry - for 60 of these stars data from the literature areused. In total 290 datasets are available because of some multipleobservations. We briefly compare the photometry obtained at differentobservatories. Small but significant differences are found. A firstanalysis of the photometry supports one of the main findings of Paper I.The, in many aspects inhomogeneous, O-rich semiregular variables oftypes SRa and SRb can be successfully split in two subgroups called the`blue' and `red'/`Mira' SRVs. A separation of the `red' SRVs fromintrinsic Miras additionally requires variability information.
| New OH/IR stars from color-selected IRAS sources. 3: A complete survey
We present the results of 1612 MHz observations conducted at the AreciboObservatory of 571 color-selected sources from the IRAS Point SourceCatalog. Of these sources we detect 132, 113 for the first time. This isthe third part of an Arecibo survey of color-selected IRAS sources. Theearlier two parts together detected a total of 268 sources of 1612 MHzemission. An analysis of the properties of the OH/IR stars detected inall three parts of the survey is included. In particular we compute thelimiting 1612 MHz peak flux of the entire survey to be approximately 40mJy. The correlation between the IRAS infrared fluxes and the 1612 MHzflux of the 132 sources detected in part III of the survey is smallerthan that found in the earlier parts of the survey. This is to beexpected from the intrinsic variability of OH/IR stars and the longertime gap between the 1612 MHz observations and the IRAS measurements. Weidentify a subset of 54 stars as being near the tangent point of thegalactic rotation curve. Using the kinematical distances to these starswe find that the efficiency of momentum transfer varies exponentiallywith the (25 - 12) micrometer color, consistent with the stellar outflowbeing driven by radiation pressure. Further the IR pump efficiencyincreases with increasing optical depth of the circumstellar shell, asexpected for radiative pumping. The bolometric luminosity function isfound to decrease sharply above LBol = 5600 solar luminosity,and the 1612 MHz luminosity function shows a corresponding falloff aboveL1612 = 1.8 x 10-8 solar luminosity. We also finddirect confirmation of the expectation that sources with large expansionvelocity are more luminous than sources with small expansion velocity.
| OH/IR star color mimics
IR color criteria are used to select potential OH/IR stars from the IRASPoint Source Catalog. These OH/IR star color mimics, despite oftenhaving thick and demonstrably O-rich dust shells to shield theirmolecules against interstellar UV, have no 1612 MHz masers. The mostlikely reason for this is that these stars have degenerate companions,which collect an accretion disk from the red giant wind, which in turnprovides them with a local source of UV to dissociate molecules fromwithin their dust shells. In some cases this self-generated UV issufficient to excise all molecules from a shell, as happens withsymbiotic novae; in some cases it merely reduces their number and theability of a shell to support a maser. It is suggested that D-typesymbiotic stars can be identified among sources with thick opaque dustshells by a persistent absence of appropriate masers: these are theOH/IR color mimics.
| 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.
| Classification of 831 two-micron sky survey sources south of +5 degrees.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1975AJ.....80.1011H&db_key=AST
| Catalogue d'étoiles variables nouvelles
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Observation and Astrometry data
| Constellation: | Orion |
| Right ascension: | 05h06m36.11s |
| Declination: | +00°32'54.7" |
| Apparent magnitude: | 8.613 |
| Proper motion RA: | -0.1 |
| Proper motion Dec: | -2.9 |
| B-T magnitude: | 10.359 |
| V-T magnitude: | 8.758 |
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