Vol 5, No 4

Evidence of Evolution in the Dense Cores in Massive Star Forming Regions

Jian-Jun Zhou, Jarken Esimbek, Ji-Xian Sun, Bing-Gang Ju, Jing-Jiang Sun


Abstract The excitation of H2O masers usually needs very high density gas, hence it can serve as a marker of dense gas in HII region. We selected a sample of H2O maser sources from Plume et al. (four with, and four without detected CS(J = 7−6) emission), and observed them in 13CO(J=1-0) and C18O (J=1-0). C18O (J=1-0) emission was detected only in three of the sources with detected CS(J=7-6) emission. An analysis combined with some data in the literature suggests that these dense cores may be located at different evolutionary stages. Multi-line observation study may provide us clues on the evolution of massive star forming regions and the massive stars themselves.


Keywords star: evolution --- galaxies: star clusters --- galaxies: stellar content

Full Text

  • There are currently no refbacks.