13CO mapping study for massive molecular cloud cores

Abstract

Using the newly installed SIS receiving system on the 13.7 m telescope at Qinghai Station of PMO, United Radio Astronomy of CAS, CO isotope13CO J= 1-0 and C18O J= 1-0 lines were observed for three sources S241, S39 and ON3. Results show that the three sources have massive cores, of which the size is ∼ 2-5 pc, masses are ∼ 103- 104M⊙. The widths of lines are also larger than those in low mass cores. And high velocity characteristics were observed for all the sources. The VLSR distribution presents rotation of the core in ON3. And all the three cores contain deeply embedded forming massive stars. The young stellar objects in S241 and ON3 seem to be moving away from their birth sites.