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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 Welchs ring about 6,400 years ago.
Very massive stars (M>100 M$_{odot}$) are very rare objects, but have a strong influence on their environment. The formation of this kind of objects is of prime importance in star formation, but observationally still poorly constrained. We report on
We have carried out a search for massive white dwarfs (WDs) in the direction of young open star clusters using the Gaia DR2 database. The aim of this survey was to provide robust data for new and previously known high-mass WDs regarding cluster membe
Sensitive and high angular resolution ($sim$ 0.4arcsec) SO$_2$[22$_{2,20}$ $to$ 22$_{1,21}$] and SiO[5$to$4] line and 1.3 and 7 mm continuum observations made with the Submillimeter Array (SMA) and the Very Large Array (VLA) towards the young massive
We present the first ultraviolet (UV) and multi-epoch optical spectroscopy of 30 Dor 016, a massive O2-type star on the periphery of 30 Doradus in the Large Magellanic Cloud. The UV data were obtained with the Cosmic Origins Spectrograph on the Hubbl
The formation process of massive stars is not well understood, and advancement in our understanding benefits from high resolution observations and modelling of the gas and dust surrounding individual high-mass (proto)stars. Here we report sub-arcseco