Dusty Cometary Globules in W5

TL;DR

This study reports the discovery of dusty cometary tails around low-mass stars in W5, indicating a short-lived phase of disk photoevaporation caused by nearby massive stars, with tail lifetimes less than 5 million years.

Contribution

First identification of dusty cometary globules in W5, providing new insights into disk evolution and photoevaporation processes in star-forming regions.

Findings

Cometary tails observed around low-mass stars in W5.

Estimated tail lifetimes are less than 5 million years.

Photoevaporation by O stars likely causes the cometary phase.

Abstract

We report the discovery of four dusty cometary tails around low mass stars in two young clusters belonging to the W5 star forming region. Fits to the observed emission profiles from 24 micron observations with the Spitzer Space Telescope give tail lifetimes < 30 Myr, but more likely < 5 Myr. This result suggests that the cometary phase is a short lived phenomenon, occurring after photoevaporation by a nearby O star has removed gas from the outer disk of a young low mass star (see also Balog et al. 2006; Balog et al. 2008).