A Massive Young Runaway Star in W49 North

Abstract

We analyzed high angular resolution 45.5 GHz images of the W49 North massive star forming region obtained in 1998 and 2016 with the Very Large Array. Most of the ultracompact HII regions show no detectable changes over the time interval of the observations. However, subcomponents B1, B2, G2a and G2c have increased its peak flux densities by values in the range of 3.8 to 21.4 \%. Most interestingly, the cometary region C clearly shows proper motions that at the distance of the region are equivalent to a velocity of 76$\pm$6 km s${}^{-1}$ in the plane of the sky. We interpret this region as the ionized bowshock produced by a runaway O6 ZAMS star that was ejected from the eastern edge of Welch's ring about 6,400 years ago.

11 pages, 6 figures,to appear in ApJ

References in corpus (5)

• Cloud Structure of Galactic OB Cluster Forming Regions from Combining Ground and Space Based Bolometric Observations
• Time Variation in G24.78+0.08 A1: Evidence for an Accreting Hypercompact H II Region?
• Radio Measurements of the stellar proper motions in the core of the Orion Nebula Cluster
• The Proper Motions of the Double Radio Source n in the Orion BN/KL Region
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Cited by in corpus (1)

• The ultracompact regions G40.54+2.59 and G34.13+0.47: A new detection of compact radio sources