Protoplanetary Disk Masses in IC348: A Rapid Decline in the Population of Small Dust Grains After 1 Myr

TL;DR

This study surveys protoplanetary disks in IC348, revealing a rapid decline in small dust grains after 1-3 million years, which impacts planet formation potential.

Contribution

It provides the first millimeter survey of disks in IC348, showing a significant decrease in disk mass compared to younger regions, indicating rapid dust evolution.

Findings

Disk masses are 2-6 Jupiter masses.

Detected disks show signs of ongoing gas accretion.

Significant reduction in small dust grains compared to younger regions.

Abstract

We present a 1.3 mm continuum survey of protoplanetary disks in the 2-3 Myr old cluster, IC348, with the Submillimeter Array. We observed 85 young stellar objects and detected 10 with 1.3 mm fluxes greater than 2 mJy. The brightest source is a young embedded protostar driving a molecular outflow. The other 9 detections are dusty disks around optically visible stars. Our millimeter flux measurements translate into total disk masses ranging from 2 to 6 Jupiter masses. Each detected disk has strong mid-infrared emission in excess of the stellar photosphere and has Halpha equivalent widths larger than the average in the cluster and indicative of ongoing gas accretion. The disk mass distribution, however, is shifted by about a factor of 20 to lower masses, compared to that in the ~1 Myr old Taurus and Ophiuchus regions. These observations reveal the rapid decline in the number of small dust grains in disks with time, and probably their concomitant growth beyond millimeter sizes. Moreover, if IC348 is to form planets in the same proportion as detected in the field, these faint millimeter detections may represent the best candidates in the cluster to study the progression from planetesimals to planets.