Search

Aims.We search for Polycyclic Aromatic Hydrocarbon (PAH) features towards young low-mass (T Tauri) stars and compare them with surveys of intermediate mass (Herbig Ae/Be) stars. The presence and strength of the PAH features are interpreted with disk radiative transfer models exploring the PAH feature dependence on the incident UV radiation, PAH abundance and disk parameters.

Aims.We present a compositional analysis of $\rm 8{-}13\,\mu m$spectra of 32 young stellar objects (YSOs). Our sample consists of 5 intermediate-mass stars and 27 low-mass stars. Although some previous studies give reasons for the similarity between the dust in circumstellar disks of T Tauri stars and Herbig Ae/Be stars, a quantitative comparison has been lacking so far. Therefore, we include a discussion of the results of the $\rm 10\,\mu$m spectroscopic survey of van Boekel et al. (2005, A&A, 437, 189), who focus on Herbig Ae/Be stars, the higher mass counterparts of T Tauri stars, and draw comparisons to this and other studies.