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A spectroscopic analysis of the DBA (or DAB) white dwarf KUV 02196+2816 ispresented. The observed hydrogen and helium line profiles are shown to beincompatible with model spectra calculated under the assumption of ahomogeneous hydrogen and helium chemical composition. In contrast, an excellentfit to the optical spectrum of KUV 02196+2816 can be achieved if the object isinterpreted as an unresolved double degenerate composed of a hydrogen-line DAstar and a helium-line DB star. The atmospheric parameters obtained from thebest fit are Teff=27,170 K and log g=8.09 for the DA star, Teff=36,340 K andlog g=8.09 for the DB star, which implies that the total mass of the system(M~1.4 Msol) is very close to the Chandrasekhar limit. Moreover, the effectivetemperature of the DB stars lies well within the so-called DB gap where veryfew bright DB stars are found. The implications of this discovery with respectto the DAB and DBA spectral classes and to the evolution of double degeneratebinaries are discussed.

Spectroscopic Analysis of the White Dwarf KUV 02196+2816: A New Unresolved DA+DB Degenerate Binary