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تسجيل مستخدم جديدA subtle IR excess associated with a young White Dwarf in the Edinburgh-Cape Blue Object Survey
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We report the discovery of a subtle infrared excess associated with the young white dwarf EC,05365--4749 at 3.35 and 4.6,$mu$m. Follow-up spectroscopic observations are consistent with a hydrogen atmosphere white dwarf of effective temperature 22,800,K and log [emph{g} (,cm,s$^{-2}$) ] = 8.19. High resolution spectroscopy reveals atmospheric metal pollution with logarithmic abundances of [Mg/H] = --5.36 and [Ca/H] = --5.75, confirming the white dwarf is actively accreting from a metal-rich source with an intriguing abundance pattern. We find that the infrared excess is well modeled by a flat, opaque debris disk, though disk parameters are not well constrained by the small number of infrared excess points. We further demonstrate that relaxing the assumption of a circular dusty debris disk to include elliptical disks expands the widths of acceptable disks, adding an alternative interpretation to the subtle infrared excesses commonly observed around young white dwarfs.
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