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Light and intermediate nuclei as well as s-process elements have been detected in presolar grains and in evolved red giants. The abundances of some of these nuclei cannot be accounted for by canonical stellar models and require non-convective mixing below the envelope, occurring during the phases of the Red Giant Branch (RGB) and of the Asymptotic Giant Branch (AGB). Similar mechanisms appear to be necessary to account for the formation of the neutron source driving s processing. We present a short review of these phenomena and we comment on the picture that emerges from the set of available data on the evolution and nucleosynthesis in low mass stars. Our conclusions include: i) the need for deep mixing in both RGB and AGB stars; ii) the suggestion that these phenomena occur at a non-negligible velocity, possibly incompatible with diffusive processes; iii) the verification that the abundances of neutron-rich nuclei are presently increasing in the Galaxy, contrary to previous expectations and hence that the s process has new surprises to offer us; iv) the recognition of the growing importance of very low mass stars for Galactic nucleosynthesis.
I briefly review recent observations of regions forming low mass stars. The discussion is cast in the form of seven questions that have been partially answered, or at least illuminated, by new data. These are the following: where do stars form in mol
We investigate the properties of star forming regions in a previously published numerical simulation of molecular cloud formation out of compressive motions in the warm neutral atomic interstellar medium, neglecting magnetic fields and stellar feedba
Many nucleosynthesis and mixing processes of low-mass stars as they evolve from the Main Sequence to the thermal-pulse Asymptotic Giant Branch phase (TP-AGB) are well understood (although of course important physics components, e.g. rotation, magneti
We investigate systematically the dynamical mass ejection, r-process nucleosynthesis, and properties of electromagnetic counterparts of neutron-star (NS) mergers in dependence on the uncertain properties of the nuclear equation of state (EoS) by empl
We analyze the relationships between atomic, neutral hydrogen (HI) and star formation (SF) in the 12 low-mass SHIELD galaxies. We compare high spectral (~0.82 km/s/channel) and spatial resolution (physical resolutions of 170 pc - 700 pc) HI imaging f