New results of presolar-grain studies and constraints on nucleosynthesis and stellar evolution Original Research Article

A new type of secondary ion mass spectrometer, the NanoSIMS, allows the elemental and isotopic analysis of smaller samples than could be measured previously. This instrument has been successfully applied to studies of new types of presolar grains in primitive meteorites and interplanetary dust particles (IDPs). Examples include O- and Mg-isotopic measurements of sub-μm spinel grains, the discovery of presolar silicates in IDPs and meteorites, and the Mg- and Ti-isotopic analysis of rare classes of presolar silicon carbide grains.