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Title: WEAK AND COMPACT RADIO EMISSION IN EARLY HIGH-MASS STAR FORMING REGIONS: II. THE NATURE OF THE RADIO SOURCES
In this study we analyze 70 radio continuum sources associated with dust clumps and considered to be candidates for the earliest stages of high-mass star formation. The detection of these sources was reported by Rosero et al. (2016), who found most of them to show weak ( < 1 mJy) and compact ( < 0.6") radio emission. Herein, we used the observed parameters of these sources to investigate the origin of the radio continuum emission. We found that at least ∼ 30% of these radio detections are most likely ionized jets associated with high-mass protostars, but for the most compact sources we cannot discard the scenario that they represent pressure-confined HII regions. This result is highly relevant for recent theoretical models based on core accretion that predict the first stages of ionization from high-mass stars to be in the form of jets. Additionally, we found that properties such as the radio luminosity as a function of the bolometric luminosity of ionized jets from low and high-mass stars are extremely well-correlated. Our data improve upon previous studies by providing further evidence of a common origin for jets independently of luminosity.  more » « less
Award ID(s):
1814063
NSF-PAR ID:
10099144
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
The Astrophysical journal
Volume:
880
ISSN:
0004-637X
Page Range / eLocation ID:
99
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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