Disk Evolution In The Three Nearby Star-forming Regions Of Taurus, Chamaeleon And Ophiuchus

We present an analysis of Spitzer-IRS spectra of T Tauri stars in Taurus, Chamaeleon, and Ophiuchus, which are three nearby star-forming regions of comparable age (1-2 Myr), but with differing environments. The IRS spectra reveal emission from dust in the inner few AU of the disk and thus probe the region where planets are thought to form. Our previous study of the Taurus region showed that significant evolution, like grain growth and settling, is already occurring in these protoplanetary disks. Here we compare signposts of disk evolution, like the degree of flaring of the disk and the strength of the silicate emission feature, among the objects in the three regions. This will further our understanding of whether the processes causing dust evolution and eventual disk clearing are universal or are influenced by the environment.

This work is supported by a NASA Postdoctoral Program Fellowship at the NASA Astrobiology Institute at the University of California, Los Angeles, administered by Oak Ridge Associated Universities through a contract with NASA.