Browsing Research Output by Subject "Stars: formation"
Now showing items 1-10 of 12
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Bow shocks in a newly discovered maser source in IRAS 20231+3440
(Oxford Univ Press, 2017)From measuring the annual parallax of water masers over 1.5 yr with VLBI Exploration of Radio Astrometry, we present the trigonometric parallax and corresponding distance of another newly identified water maser source ... -
Class II 6.7 GHz methanol maser association with young massive cores revealed by ALMA
(IOP, 2017)We explored the implication of the association (or lack of it) of 6.7 GHz class II methanol (CH3OH) masers with massive dense cores (MDCs) detected (within a sample of ATLASGAL selected infrared quiet massive clumps) at ... -
Detection of new methanol maser transitions associated with G358.93−0.03
(Oxford Univ Press, 2019)We report the detection of new 12.178, 12.229, 20.347, and 23.121 GHz methanol masers in the massive star-forming region G358.93−0.03, which are flaring on similarly short time-scales (days) as the 6.668 GHz methanol masers ... -
Discovery of periodic class II methanol masers associated with G339.986−0.425 region
(Oxford Univ Press, 2016)10 new class II methanol masers from the 6.7-GHz Methanol Multibeam survey catalogues III and IV were selected for a monitoring programme at both 6.7 and 12.2 GHz with the 26-m Hartebeesthoek Radio Astronomy Observatory ... -
The extraordinary outburst in the massive protostellar system NGC 6334I-MM1: flaring of the water masers in a north-south bipolar outflow driven by MM1B
(IOP Publishing, 2018)We compare multi-epoch sub-arcsecond Very Large Array imaging of the 22 GHz water masers toward the massive protocluster NGC 6334I observed before and after the recent outburst of MM1B in (sub)millimeter continuum. Since ... -
An extraordinary outburst in the massive protostellar system NGC 6334I-MM1: quadrupling of the millimeter continuum
(IOP, 2017)Based on sub-arcsecond Atacama Large Millimeter/submillimeter Array (ALMA) and Submillimeter Array (SMA) 1.3 mm continuum images of the massive protocluster NGC 6334I obtained in 2015 and 2008, we find that the dust emission ... -
A masing event in NGC 6334I: contemporaneous flaring of hydroxyl, methanol, and water masers
(Oxford Univ Press, 2018)As a product of the maser monitoring program with the 26 m telescope of the Hartebeesthoek Radio Astronomy Observatory (HartRAO), we present an unprecedented, contemporaneous flaring event of 10 maser transitions in hydroxyl, ... -
NH 3 observations of the S235 star-forming region: dense gas in inter-core bridges
(Oxford Univ Press, 2019)Star formation is thought to be driven by two groups of mechanisms; spontaneous collapse and triggered collapse. Triggered star formation mechanisms further diverge into cloud–cloud collision (CCC), “collect and collapse” ... -
NH3 observations of the S235 star-forming region: dense gas in inter-core bridges
(Oxford Univ Press, 2019)Star formation is thought to be driven by two groups of mechanisms; spontaneous collapse and triggered collapse. Triggered star formation mechanisms further diverge into cloud–cloud collision (CCC), “collect and collapse” ... -
Periodic variability of the mainline hydroxyl masers in G9.62+0.20E
(Oxford Univ Press, 2019)We present the results of a monitoring campaign using the KAT-7 and HartRAO 26 m telescopes, of hydroxyl, methanol, and water vapour masers associated with the high-mass star-forming region G9.62+0.20E. Periodic flaring ...