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Project Progress

The main focus of our efforts under Task 1 during this reporting period has been on placing constraints on the initial abundance of ⁶⁰Fe in the early Solar System. If present in sufficient abundance (i.e., ⁶⁰Fe/⁵⁶Fe >~5 ×10-7), this radionuclide would serve as a “smoking gun” for the late injection of ⁶⁰Fe by a supernova into the early Solar System, and as a significant heat source for the dehydration/differentiation of planetesimals. This work is being conducted primarily by graduate student Lev Spivak-Birndorf under the supervision of Co-I Meenakshi Wadhwa; two conference abstracts were submitted and a manuscript is currently under preparation.

Another project conducted during this reporting period was the U-Pb and Al-Mg chronology of a unique basaltic achondrite (NWA 2976), which has implications for the homogeneity of the ²⁶Al extinct radionuclide, which played a significant role in the dehydration/differentiation of planetesimals. This work was performed mainly by research associate Audrey Bouvier under the supervision of Co-I Meenakshi Wadhwa, and resulted in the publication of a manuscript in Geochimica Cosmochimica Acta.

Finally, a new project is currently being initiated on identification of refractory inclusions in chondrites with fractionation and unknown Nuclear (FUN) effects. The ultimate goal of this project is to identify FUN inclusions for precise age dating, which would potentially allow us to constrain the timing of ²⁶Al injection into the early Solar System. During this reporting period, we have developed the analytical methodologies for high precision Ti isotope analyses by laser ablation multicollector inductively coupled plasma mass spectrometer, since FUN inclusions are known to contain large mass independent isotope effects in a variety of elements including Ti.