Are Large, Cometary-Shaped Proplyds really (free-floating) EGGs?

Abstract

We report the detection of strong and compact molecular line emission (in the CO J=3-2, 4-3, 6-5, 7-6, 13CO J=3-2, HCN and HCO+ J=4-3 transitions) from a cometary-shaped object (Carina-frEGG1) in the Carina star-forming region (SFR) previously classified as a photoevaporating protoplanetary disk (proplyd). We derive a molecular mass of 0.35 Msun for Carina-frEGG1, which shows that it is not a proplyd, but belongs to a class of free-floating evaporating gas globules (frEGGs) recently found in the Cygnus SFR by Sahai, Morris & Claussen (2012). Archival Adaptive Optics near-IR (Ks) images show a central hourglass-shaped nebula. The derived source luminosity (about 8-18 Lsun), the hourglass morphology, and the presence of collimated jets seen in HST images, imply the presence of a jet-driving, young, low-mass star deeply embedded in the dust inside Carina-frEGG1. Our results suggest that the true nature of many or most such cometary-shaped objects seen in massive SFRs and previously labelled as proplyds has been misunderstood, and that these are really frEGGs.

accepted to Astrophysical Journal (Letters)

References in corpus (7)

• The Large APEX Bolometer Camera LABOCA
• Photoevaporating Proplyd-like objects in Cygnus OB2
• APECS - The Atacama Pathfinder Experiment Control System
• A (sub)millimetre study of dense cores in Orion B9
• Spitzer/MIPS 24 micron Detection of Photoevaporating Protoplanetary Disks
• Shocked and Scorched: The Tail of a Tadpole in an Interstellar Pond
• Dusty Cometary Globules in W5

Cited by in corpus (14)

• Distributed star formation throughout the Galactic Center cloud Sgr B2
• Proplyds around a B1 star - 42 Orionis in NGC 1977
• Disk Dispersal: Theoretical Understanding and Observational Constraints
• Filament formation in wind-cloud interactions. II. Clouds with turbulent density, velocity, and magnetic fields
• Proper motions of collimated jets from intermediate-mass protostars in the Carina Nebula
• [Fe II] jets from intermediate-mass protostars in Carina
• The tiny globulettes in the Carina Nebula
• Protoplanetary disks in the hostile environment of Carina
• ALMA Observations of the Extraordinary Carina Pillars: HH 901/902
• Radio observations of globulettes in the Carina Nebula
• Probing X-ray photoevaporative winds through their interaction with ionising radiation in cluster environments: the case for X-ray proplyds
• Illuminating a tadpole's metamorphosis II: observing the on-going transformation with ALMA
• Radio observations of evaporating objects in the Cygnus OB2 region
• Shock waves in Interstellar Cloud-Cloud and Wind-Cloud Collisions