RSAA Colloquia / Seminars / Feast-of-Facts: Thursday, 02 June 2016, 11:00-12:00; Duffield Lecture Theatre

Nienke van der Marel

"Planet formation in the ALMA era: gas and dust in protoplanetary disks"

Protoplanetary disks are the birth cradles of planets, but the planet formation process is still not well understood. Of particular interest are the so-called transitional disks: disks with large inner cavities. In recent years, ALMA has revealed that gas and dust show different structures in these disks. Most remarkable is the discovery of strong asymmetries in the dust continuum emission in some of these disks, whereas the gas shows a full Keplerian disk. These asymmetries can be interpreted as dust traps, places where dust particles concentrate and grow. Multi wavelength observations confirm an increase in dust growth in the center of these dust traps. On the other hand, the gas distribution as mapped by high spatial resolution CO observations reveals gas cavities at smaller radii than their dust counterparts, hinting at the presence of already formed Jupiter-like planets. This phenomenon turns out to be common in transition disks with large cavities in various studies. In this talk I will discuss the new structures found with ALMA and their implications for our understanding of planet formation.