by LI Juan

Thank to the  newly built 9-pixel 3-mm heterodyne receivers of the PMO 14m telescope, a  group of astronomers from Nanjing University (NJU) and Purple Mountain  Observatory (PMO) studied the kinematic structure and magnetic fieldin  dense molecular gas cores. The PMO 14m telescope  in Delingha was used  to observe the emission of molecules in molecular cores of high density  in 27 Giant Molecular Clouds(GMCs) of our Milky Way.

In GMCs,  newborn massive stars are hidden from visual respect, and the densegas  clouds are still collapsing and forming more stars. Using multiple  molecular gas tracers, which are excited in different physical  conditions, evidence was found to support the chemical evolution of C2H  molecule. It is for the first to support the "chemical clock" for C2H to  diagnostic the life evolution and formation o  massive stars.

From the  moving information of the gas clouds, i.e. Dynamics, the energy transfer  was studied. The energy from angular momentum to was found to be  decreasing from outer region to inner regions of the GMC cores, implying  that the magnetic force is playing an important role in GMCs. The  magnetic field of the GMCs was derived from the molecular emission and  simple models.

These results were recently published in the Astrophysical Journal, Volume 745,Issue 1, article id. 47 (2012).http://adsabs.harvard.edu/abs/2012ApJ...745...47L