Discovery of New Candidate Vega-type Systems from IRAS and the 2 Micron All-Sky Survey

August 2000 • 2000ApJ...538L.155F

Authors • Fajardo-Acosta, Sergio B. • Beichman, Charles A. • Cutri, Roc M.

Abstract • We obtained J (1.25 μm), H (1.65 μm), and K_s (2.17 μm) photometry from the 2 Micron All-Sky Survey and 12, 25, 60, and 100 μm photometry from the IRAS Faint Source Catalog of 2834 field stars. We identified in this sample 296 main-sequence (luminosity class IV, IV-V, or V) stars. We searched the sample of main-sequence stars for excess 12 μm emission with respect to J, H, and K_s photospheric emission. We discovered eight systems with 12 μm excess emission newly reported here. These excesses are likely to be from Vega-type circumstellar dust, but small-aperture photometry is needed to confirm their nature. Preliminary models that assume the excesses are circumstellar show the dust to be located ~1-10 AU from the stars, where it is heated to ``terrestrial'' temperatures, ~200-500 K. Colder dust might also exist in the systems but below the IRAS sensitivity limit. The exception is HD 93331 (B9.5 V), previously known for its IRAS far-infrared excess.

Links

• SIMBAD http://simbad.u-strasbg.fr/simbo.pl?bibcode=2000ApJ...538L.155F
• PDF https://iopscience.iop.org/article/10.1086/312815/pdf
• ELECTR https://doi.org/10.1086%2F312815