Infrared Space Observatory Mapping of 60 Micron Dust Emission around Vega-Type Systems
Stencel, R. E.; Backman, D. E.; Fajardo-Acosta, S. B.
United States
Abstract
We mapped 60 μm emission around five Vega-type systems. We utilized the PHOT-C100 far-infrared array camera on board the Infrared Space Observatory. The spatial resolution of the maps is ~30". The maps of three sources (α CrB, σ Her, and α Cen) do not show any evidence of extended emission. The map of γ Oph shows marginal hints of extended emission ~30" (800 AU) from the star. The map of α PsA shows extended emission ~30"-80" (~210-560 AU) from the star. This location, together with α PsA's characteristic IRAS temperature of 58-75 K, suggest the observed dust grains around α PsA are up to ~10 μm in size. We estimate the mass of dust grains emitting the IRAS 60 μm excess of α PsA to be ~(2-6) ×10-3 M⊕.
Based on observations with ISO, an ESA project with instruments funded by ESA member states, with the participation of ISAS and NASA.