Hsi-Wei Yen (ASIAA); Pin-Gao Gu (ASIAA)
Growth of dust grains to larger aggregates and further to planetesimals is an important step in the standard core accretion scenario of planet formation. In this presentation, I will introduce our recent study on the mechanisms of dust concentration, which may enhance grain growth, in the protoplanetary disk around a pre-main sequence star HD142527. We analyzed the ALMA archival data of the continuum at six wavelengths from 3 to 0.4 mm and the CO isotopologue lines at multiple transitions to estimate the dust and gas density and thus gas-to-dust mass ratio in the HD142527 disk. In addition, we analyzed the disk rotation traced by the molecular lines and identified a region with non-Keplerian rotation, suggestive of a local pressure bump. We found that this region with non-Keplerian rotation has a higher dust density and a lower gas-to-dust mass ratio compared to the mean values in the disk. I will discuss these results in the context of dust trapping and feedback in the pressure bump in the HD142527.