A survey of protoplanetary disks in the Taurus star forming region at millimeter wavelengths

Protoplanetary disks are dense regions of gas and dust rotating around a young T-Tauri stars. In this thesis, we discuss the results of our study of 97 single Class II Young Stellar Objects (YSOs) in the Taurus star forming region at sub-mm/mm wavelengths. The main focus of our study was to examine the relationship between the spectral index, fluxes at mm-wavelengths and various stellar properties, as well as the correlation between the mass of the central star and the mass of dust in the disk. We re-scaled stellar luminosities using the updated Gaia DR2 distances and estimated stellar masses using pre-main sequence evolutionary tracks. We also estimated dust masses from the flux densities at 3 mm by adopting assumptions regarding other disk properties. From the 97 sources in our sample 51 were detected at wavelengths of 0.89 mm and 1.33 mm using the Sub-Millimeter Array and at a wavelength of 3 mm using The Combined Array for Research in Millimeterwave Astronomy, an additional 6 disks were detected at only two of the aforementioned wavelengths. This allowed for an estimation of the spectral index values for these disks. The spectral index at millimeter wavelengths of the dust emission in disks can give us information on the properties of the emitting dust such as optical depth, grain sizes, and distributions. We found that about 75% of the disks in our sample are optically thin at sub-mm/mm wavelengths. We estimated that ∼ 50% of the disks in our sample have dust masses Mdust ≥ 5M⊕ and ∼ 30% of the disks have dust masses Mdust ≥ 10M⊕. We also confirmed the existence of a strong correlation between the dust masses in the disk and the host stellar masses. This study will allow us to refine scaling laws linking disk and stellar properties, and shed light on the origin of some of the key scaling laws recently observed from the known population of exoplanets.