A search for High Mass Stars Forming in Isolation using CORNISH & ATLASGAL

Abstract

Theoretical models of high mass star formation lie between two extreme scenarios. At one extreme, all the mass comes from an initially gravitationally-bound core. At the other extreme, the majority of the mass comes from cluster scale gas, which lies far outside the initial core boundary. One way to unambiguously show high mass stars can assemble their gas through the former route would be to find a high mass star forming in isolation. Making use of recently available CORNISH and ATLASGAL Galactic plane survey data, we develop sample selection criteria to try and find such an object. From an initial list of approximately 200 sources, we identify the high mass star forming region G13.384+0.064 as the most promising candidate. The region contains a strong radio continuum source, that is powered by an early B-type star. The bolometric luminosity, derived from infrared measurements, is consistent with this. However, sub-millimetre continuum emission, measured in ATLASGAL, as well as dense gas tracers, such as HCO+(3-2) and N2H+(3-2) indicate that there is less than 100 M${}_{\odot }$ of material surrounding this star. We conclude that this region is indeed a promising candidate for a high mass star forming in isolation, but that deeper near-IR observations are required to put a stronger constraint on the upper mass limit of young, lower mass stars in the region. Finally, we discuss the challenges facing future studies in proving a given high mass star is forming in isolation.

10pages, 6 figures, accepted for publication in PASA

References in corpus (10)

• The UKIRT Infrared Deep Sky Survey (UKIDSS)
• Radiation-Hydrodynamic Simulations of Collapse and Fragmentation in Massive Protostellar Cores
• Star formation through gravitational collapse and competitive accretion
• Kinematic Distances to Molecular Clouds identified in the Galactic Ring Survey
• Resolution of the Distance Ambiguity for Galactic HII Regions
• ATLASGAL --- properties of compact HII regions and their natal clumps
• Do O-stars form in isolation?
• The Bolocam Galactic Plane Survey. X. A Complete Spectroscopic Catalog of Dense Molecular Gas Observed toward 1.1 mm Dust Continuum Sources with 7.5 <= l <= 194 degrees
• The influence of multiple stars on the high-mass stellar initial mass function and age-dating of young massive star clusters
• Discovery of Star Formation in the Extreme Outer Galaxy Possibly Induced by a High-velocity Cloud Impact

Cited by in corpus (2)

• The Co-Ordinated Radio and Infrared Survey for High-Mass Star Formation. V. The CORNISH-South Survey and Catalogue
• A Low Frequency Pilot Survey of Southern HII Regions in the Vela Constellation