Aperture Synthesis Imaging of V892 Tau and PV Cep: Disk Evolution

TL;DR

This study uses high-resolution interferometry to resolve and compare the disks of two Herbig Ae stars at different evolutionary stages, revealing differences in dust growth and disk mass that inform disk evolution processes.

Contribution

First resolved disks of V892 Tau and PV Cep, providing insights into dust growth and disk evolution in Herbig Ae stars at different ages.

Findings

V892 Tau has a low dust opacity index indicating large grain growth.

PV Cep has a high opacity index and a more massive, less evolved disk.

PV Cep's dust evolution appears slower than T Tauri stars.

Abstract

I present a study of two Herbig Ae stars that are in completely different evolutionary stages: V892 Tau and PV Cep. Using sub arc-second interferometric observations obtained with the Combined Array for Research in Millimeter-wave Astronomy (CARMA) at the 1.3 and 2.7 mm wavelengths, I have for the first time resolved their disks. I deduce that the 5 Myr old V892 Tau has a low dust opacity index $\beta$=1.1 and a disk mass of 0.03 $\msun$. These values correspond to the growth of its dust into large up to centimeters size structures. In contrast, the very young (a few 10$^5$yrs) PV Cep has a quite high opacity index $\beta$ =1.75 and a more massive disk 0.8 $\msun$. PV Cep has the youngest resolved disk around any Herbig Ae star. Unlike the youngest T Tauri and Class 0 stars, which contain large and processed grains, the young Herbig Ae star, PV Cep, disk contains ISM-like unprocessed dust. This suggests that PV Cep's dust evolution is slower than T Tauri stars'. I also present high spatial resolution interferometric observations of the PV Cep outflow. The outflow inclination is consistent with the orientation of the known Herbig-Haro flow in that region, HH315.