Discovery of a Nearly Edge-on Disk around HD 32297

Abstract

We report the discovery of a nearly edge-on disk about the A0 star HD 32297 seen in light scattered by the disk grains revealed in NICMOS PSF-subtracted coronagraphic images. The disk extends to a distance of at least 400 AU (3 .3) along its major axis with a 1.1 mm flux density of 4.81 0.57 mJy beyond a radius of 0 .3 from the coronagraphically occulted star. The fraction of 1.1 mm starlight scattered by the disk, 0.0033 0.0004, is comparable to its fractional excess emission at 25 60 mm of ∼0.0027 as measured from IRAS data. The disk appears to be inclined 10 .5 2 .5 from an edge-on viewing geometry, with its major axis oriented 236 .5 1 eastward of north. The disk exhibits unequal brightness on opposing sides and a break in the surface brightness profile along the NE-side disk major axis. Such asymmetries might implicate the existence of one or more (unseen) planetary mass companions.