SIMBAD references

A search for previously undetected optically thin disks around stars in the nearby, young, TW Hydrae Association (TWA) was conducted around 16 stars with sensitive 12 and 18 µm photometry. The survey could detect zodiacal-like dust, with temperature 200-300 K, at levels of L_IR/L_*=7x10^–3. Possible mid-infrared excess emission from TWA 17 was detected at the 2 σ level, but none of the other stars showed evidence for circumstellar dust. The rapid disappearance of large amounts of dust around the K- and M-type stars in this sample may mean that any planet formation in the terrestrial planet region was completed very quickly. There appears to be a bimodal distribution of dust disks in TWA, with stars having either copious or negligible warm dust.