6 Summary

The main results of our study are as follows:

We find strong H₂ shock emission around the $\sim$10$M_\odot$ protostar S140 IRS1. Some of these shocks are related to the well known $\sim$160$^\circ$/340$^\circ$ CO outflow, but the strongest shocks are found in the $20\hbox{$^\circ$ }/200\hbox{$^\circ$ }$ outflow, which seems to be currently very active. These results provide evidence for the existence of two distinct bipolar outflow systems originating simultaneously from IRS1. The $\sim$8-10$M_\odot$ protostars IRS1-3 are associated with a cluster of fainter sources, presumably lower-mass young stellar objects. The total mass in stars seems to exceed the mass of the remnant gas and dust in the S140 region significantly. This might indicate that the strong outflows of the protostars have expelled most of the gas from the region.

Acknowledgements

We would like to thank the Calar Alto staff for their support during our observations and Thomas Stanke for assistance in the data reduction. MDS is grateful to G. Weigelt for support and discussions during visits to the MPIfR.