The molecular environment of the young cluster of Class 0 young stellar objects (YSOs) located in the globule CB34 has been investigated through a multiline millimetre survey. The CO, 13CO, C18O and CS emissions show that the present star-forming process is concentrated into three molecular clumps with the size of ~0.25 pc, which are embedded in a cool more extended gas. The spatial distribution of the high-velocity emission reveals the occurrence of multiple outflows which are associated with the brightest YSOs. The interaction of the outflows with the molecular clumps has been studied by using the abundances of products of shocked chemistry such as SiO and SO. The abundances of these molecules at the high velocities of the outflows can be used to further specify, with respect to the continuum results, the characteristics of the Class 0 YSOs. In particular, one of the YSOs which does not show the presence of SiO and SO at high velocities is thought to be in a more evolved phase where most of the molecules produced at high velocities in the shocked regions have been already destroyed.
The young cluster in the CB34 globule: the clumps and the outflows
2003
Abstract
The molecular environment of the young cluster of Class 0 young stellar objects (YSOs) located in the globule CB34 has been investigated through a multiline millimetre survey. The CO, 13CO, C18O and CS emissions show that the present star-forming process is concentrated into three molecular clumps with the size of ~0.25 pc, which are embedded in a cool more extended gas. The spatial distribution of the high-velocity emission reveals the occurrence of multiple outflows which are associated with the brightest YSOs. The interaction of the outflows with the molecular clumps has been studied by using the abundances of products of shocked chemistry such as SiO and SO. The abundances of these molecules at the high velocities of the outflows can be used to further specify, with respect to the continuum results, the characteristics of the Class 0 YSOs. In particular, one of the YSOs which does not show the presence of SiO and SO at high velocities is thought to be in a more evolved phase where most of the molecules produced at high velocities in the shocked regions have been already destroyed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
