5 mars 2021
Title: How do stars get their mass? Understanding the origin of the IMF from the mass distribution of cores
Speaker: Dr. Thomas Nony (UNAM)
Abstract:
The origin of stellar masses is one of the most central open issues in astrophysics. In this talk, I will introduce the ALMA-IMF Large Program, whose goal is to determine if and how the origin of the Initial Mass Function (IMF) depends on the cloud characteristics. Its first results, obtained from a large sample of cores without significant bias, suggest that mass distribution of cores (CMFs) in high-mass proto-clusters generally do not follow the canonical IMF.
I will also present our recent detailed studies of the W43-MM2&MM3 molecular complex. We propose that top-heavy CMFs are associated with spatially and temporally limited bursts of star formation. In addition, the identification of outflows in CO(2-1) enables us to assess that a very large fraction of the excess high-mass cores are protostellar. This confirms that the high-mass prestellar core phase, if it exists, is evanescent. Interestingly, protostellar outflows in W43 have also shown clear evidence of episodicity, bringing new elements toward the understanding of episodic accretion.