Fragmentation and age of massive star-forming regions

Abstract:
In the last decade, we have started to spatially resolve the relatively small gas and dust condensations in high-mass 
star-forming regions that will eventually become a massive star or system. We call these condensations of sizes on the order 
of 0.01 pc “cores”, and by estimating their masses we can construct the so-called Core Mass Function (CMF) of a region, to 
compare with the IMF and try to determine the evolutionary process from a core to a star.
For massive star-forming regions, the relationship between the CMF and the IMF is not yet well understood. This is, among 
other factors, due to the fact that there are not many massive CMF determined.
Even then, some of those few CMF seem to tell a story of evolution, by presenting different slopes than that of the Salpeter IMF 
while others, seem to be very similar to the IMF.
Are we in fact observing regions at different evolutionary stages? One way to answer that is by determining the relative age of 
those regions, something that can be done by estimating their deuteration. In this talk I will show you the CMFs we obtained for 
a group of massive star-forming regions with SMA and PdBI observations. These CMFs show different slopes, and we have 
obtained spectral observations of deuterated molecules to attempt to establish an age scale among them.