SIMBAD references

The problem of detecting Jovian-sized planets orbiting white dwarf stars is considered. Significant IR excesses result from warm Jupiters orbiting a white dwarf of T_eff=10,000 K at a distance of ∼10³ white dwarf radii (corresponding to ∼10² Jupiter radii or a few tenths of an AU) with an orbital period of ∼100 days. Such a planet will have a 10 µm flux density at its Wien peak that is comparable to the emission of the white dwarf at that wavelength. Although the white dwarf is much hotter than the planet, the planet will have peak brightness at the IR, well into the Rayleigh-Jeans tail of the white dwarf; plus, Jovians are about 10 times larger than white dwarfs, so there is a substantial gain in the planet-to-star brightness contrast as compared to planets around main-sequence stars. In the solar neighborhood, there are 51 white dwarf stars within 13 pc of the Sun. At 10 pc, the IR flux density of ``warm'' Jupiters (a few hundred kelvins) will fall in the range 10-100 µJy, which should be observable with SIRTF.