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On the far-infrared excess of Vega
Nature, 1984The Infrared Astronomy Satellite (IRAS) has recently detected a compact far-infrared emission source associated with Vega (α Lyrae)1. This flux appears to be thermal emission from dust heated by the visual/UV luminosity of Vega. Although circum-stellar dust is commonly associated with young, early-type stars2, the characteristics of the emission from ...
Paul M. Harvey +2 more
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Near infrared excesses in Be stars
Publications of the Astronomical Society of the Pacific, 1981Sixty-eight bright Be stars were observed in the R and I bands of the Johnson system. Nearly all of them lie above the main sequence in a (B - V,V- I) diagram, which is interpreted as a near-infrared excess (ΔI) in their energy distributions. From the computed difference with the standard main-sequence relation, a correlation of this ΔI value with the ...
A. Feinstein, H. G. Marraco
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Millimetre photometry and infrared spectroscopy of Vega-excess stars
Astrophysics and Space Science, 1994JCMT millimetre-wave detections have been obtained for 11 Vega-excess stars having spectral types ranging from B9 to K5. UKIRT l0-μm spectra have been obtained for two of the sources, SAO 179815 and SAO 186777. The spectrum of SAO 179815 shows an unusually broad and diffuse silicate emission feature, whilst SAO 186777 shows the unidentified infrared ...
R. J. Sylvester +2 more
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Infrared excesses of barium stars
2008A sample of thirty-one barium stars has been studied using JHKLMN photometry. Infrared excesses are found to occur in the H, M, and N bands. The H-excess appears to correlate with the barium intensity (defined by the abnormal strength of the 4554 A BaII line), whereas the excesses in M and N do not.
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Search for bright stars with infrared excess
AIP Conference Proceedings, 2014Bright stars, stars with visual magnitude smaller than 6.5, can be studied using small telescope. In general, if stars are assumed as black body radiator, then the color in infrared (IR) region is usually equal to zero. Infrared data from IRAS observations at 12 and 25μm (micron) with good flux quality are used to search for bright stars (from Bright ...
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Infrared excess in Wolf-Rayet stars
Astrophysics and Space Science, 1986On the basis of continuum energy distributions in the wavelength region λλ3200–11 000 A, effective temperature for 14 Wolf-Rayet stars are estimated by comparing with Kurucz (1979) model atmospheres. The continuum energy distribution curve shows strong infrared excess emissions above of λ5000 A in every star.
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Mid Infrared Excess and Ultraviolet Extinction
1987Correlations between the mid infrared excess and the UV extinction parameters are investigated, using a sample of 50 stars reported to have peculiar extinction properties. No correlation is found between the mid infrared excess and the 2175 A extinction bump, suggesting that the carriers of the UV bump and the mid infrared emission are different.
COX, P, LEENE, A
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The Infrared Excess From Stellar Winds
1986The IR excess can be used to study the density or velocity structure in the lower parts of the winds of early type stars. The depth of the emitting region and the excess in magnitudes is given for typical O-stars, as a function of λ and Ṁ. The first results of an ongoing study of the IRAS data are discussed briefly.
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Infrared Excess Sources in the Galactic Center Stellar Cluster
2005We present results from diffraction-limited L -band spectroscopy and H, K, and L -band imaging of the IRS 13 region in the Galactic Center performed with the new adaptive optics camera NAOS/CONICA at the ESO VLT. We have discovered a small ( 0.13 l.y. diameter) cluster of compact sources about 0.5 arcsec north of IRS 13 with strong IR excesses due to T>
Eckart, A. +7 more
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