Accurate Measurement of Protoplanetary Disc Masses

Establish robust, empirically validated methodologies to measure the masses of protoplanetary discs around young stars using molecular gas tracers and submillimetre dust continuum emission, quantifying uncertainties and resolving the current discrepancy between disc mass estimates and exoplanet population requirements.

Background

The paper highlights that protoplanetary discs are central to planet formation studies and that over the last decade ALMA has revolutionized high-resolution disc imaging. Despite this progress, reliably determining disc masses remains difficult, which underpins the so-called “missing mass” problem: disc mass estimates often appear insufficient to form the observed exoplanet population.

The authors note that both gas-tracer-based and dust-continuum-based approaches yield inconsistent or inadequate mass estimates, motivating deeper, systematic multi-line and continuum observations, and improved modeling frameworks to overcome this unresolved issue.