SIMBAD references

We report results of a sensitive search for cold dust and molecular gas in the disks around eight T Tauri stars in the high-latitude cloud MBM 12. Interferometric observations of 3 mm continuum emission in five fields containing six of the objects and literature values for the remaining two limit the disk masses to M_disk<0.04-0.09 M_☉(gas plus dust), for a gas-to-dust mass ratio of 100 and a distance of 275 pc. By co-adding the 3 mm data of our five fields, we set an upper limit to the average disk mass of M{d1}_disk(N=5)<0.03 M_☉. Simultaneous observation of the CS J=2-1 and the N₂H⁺ 1-0 lines show no emission. Single-dish observations of the ¹³CO 2-1 line limit the disk mass to (5-10)x10^–4 M_☉for a standard CO abundance of 2x10^–4. Depletion of CO by up to 2 orders of magnitude through freezing out or photodissociation can reconcile these limits. These mass limits lie within the range found in the Taurus-Auriga and ρ Oph star-forming regions (0.001-0.3 M_☉) and preclude conclusions about possible decrease in disk mass over the 1-2 Myr age range spanned by the latter two regions and MBM 12. Our observations can exclude the presence in MBM 12 of T Tauri stars with relatively bright and massive disks such as T Tau, DG Tau, and GG Tau.