JKAS - Journal of the Korean Astronomical Society

The Korean Astronomical Society

JKAS is a bimonthly publication of the Korean Astronomical Society. We aim at promoting the original work of researchers in all branches of astronomy and astrophysics. We cover all categories of work, including observation, theory, methodology, instrumentation, software, and data bases. We welcome proposals for review articles or special issues.

JKAS was launched in 1968 to provide a peer-reviewed scientific journal to the Korean community of astronomers. As there were only a few professional astronomers in Korea back then, JKAS initially published one issue per year, with each issue containing a handful of papers written either in Korean or English. The first-ever JKAS paper was written by Chou & Kitamura and discussed the photometric orbit of the eclipsing binary DI Pegasi. Over time, the Korean astronomy community grew, and so did the number of papers. In 1986, JKAS became English-only, with Korean language papers spun off to the Publications of the Korean Astronomical Society (PKAS). Around 2004/2005, the astronomical societies of Korea, Japan, China, and India discussed a merger of their national astronomy journals, including JKAS, into a unified Asian journal; eventually, this proposal was rejected In the past decade, efforts were made to make JKAS fit for the 21st century. In 2009, JKAS was added to the ISI/Thomson Reuters Science Citation Index Expanded database and received an impact factor, thus at last joining the family of globally recognized quality scientific journals. Nowadays, JKAS receives about 40 to 50 papers per year out of which 20 to 30 are accepted and published.

Journal of the Korean Astronomical Society - Vol. 53 , No. 3

53: 77 - 85, 2020 June





In the molecular cloud G33.92+0.11A, massive stars are forming sequentially in dense cores, probably due to interaction with accreted gas. Cold dense gas, which is likely the pristine gas of the cloud, is traced by DCN line and dust continuum emission. Clear chemical differences were observed in different source locations and for different velocity components in the same line of sight. Several distinct gas components coexist in the cloud: the pristine cold gas, the accreted dense gas, and warm turbulent gas, in addition to the star-forming dense clumps. Filaments of accreted gas occur in the northern part of the A1 and A5 clumps, and the velocity gradient along these features suggests that the gas is falling toward the cloud and may have triggered the most recent star formation. The large concentration of turbulent gas in the A2 clump seems to have formed mainly through disturbances from the outside.

Key words: ISM: molecules, radio lines: ISM, stars: formation

Received 04 Dec 2019 Accepted 08 Jun 2020