Analytical work (see details at project website
https://konkoly.hu/staff/peto.maria/IPUSS/)(s’ouvre dans une nouvelle fenêtre):
The IPUSS project studied high metamorphic grade ordinary chondrites, phosphate mineral separates, Calcium Aluminum rich inclusions (CAIs) from CV3 primitive carbonaceous chondrites and differentiated meteorites. Trace element data was obtained on the same sample aliquots destroyed for noble gas analysis. Most data was obtained with quadrupole inductively coupled mass spectrometry and for phosphates with neutron activation analysis. The analytical work also involved successful neutron irradiation of some of the studied samples. The noble gas analysis on CAIs was obtained on exceptionally large amount of material, and Mg isotope analysis was necessary for mapping out nucleosynthetic variations of studied inclusions. Noble gas isotope analysis at the secondment included furnace experiments, laser extraction development and testing, and laser experiments. Noble gas isotope data has been obtained on ordinary chondrites, CAIs and phosphates. Although the dataset for the latter two sample group is incomplete, we have the funds to complete the experiments at the secondment within 8 months from the end date of the MSCA.
Results (including exploitations and dissemination)
1. The project obtained a complementary set of meteorite samples that is for the first time adequate to explain the variation of the initial Pu/U ratio in the early Solar System. The project successfully developed a comprehensive experimental approach that includes high precision noble gas isotope analysis in combination with trace element analysis on the very same samples. The dataset will be published shortly as a first-author paper (Pető M. K., Busemann H., Jacobsen S., Wang K., Wehmeyer B,. Sedagatpour F., Lugaro M., Gmeling K., Petaev M., Ott U. A new estimate of the initial 244Pu content of the early Solar System, to be submitted to Geochimica et Cosmochimica Acta)
2. The project mapped the high precision Mg isotopic composition of 22 CAIs, which lead to the unexpected discovery of strong nucleosynthetic anomaly in a “FUN” CAI. The finding is unique and exciting because this type of anomalous material could be dated with U-Pb for the first time, and can shed light on the timing of the addition of another short-lived radioactive nucleus 26Al to the pre-solar nebula, whose decay acted as the main heat source in the first few million years. Pető has been involved in the Mg and Ca isotopic characterization of the FUN CAI. The result was presented as an invited talk at Goldschmidt Conference in 2018 and will be published as a first-author paper (Pető M. K., Sedagatpour., Jacobsen S B. A new type of FUN CAI, to be submitted to Geochimica et Cosmochimica Acta)
3. Pető has co-authored an invited review paper in the journal Lithos that summarizes recent observations and the current understanding of the degassing history of the Earth’s mantle. This work is a milestone for her ongoing modeling of terrestrial volatile degassing and the re-evaluation of the Pu-I-Xe chronometry.
(Parai R., et al., 2019, The emerging portrait of an ancient, heterogeneous and continuously evolving plume source. Lithos 346-347, 1-16.)
4. Pető has been actively involved in the scientific discussions on the origin of r-process nuclei and galactic chemical evolution within the host group at Konkoly Observatory. She collaborates more closely with Benjamin Wehmeyer, with whom she is developing a simplified Galaxy model that includes some of the recently understood features of heterogeneaous galactic chemical evolution. This model will be used within the paper in preparation to interpret the new 244Pu analytical data.
5. Additional collaborative work of Pető with University of St Louis, USA involved characterizing the cosmogenic noble gas nuclide abundances and exposure ages in meteorites suitable for K isotope research (Zhao C., et al., 2019 Potassium isotopic compositions of enstatite meteorites. Meteoritics and Planetary Science, 1-14; Bloom H., et al. Potassium Isotope Compositions of Carbonaceous and Ordinary Chondrites: Implications on the Origin of Volatile Depletion in the Early Solar System, accepted to Geochimica et Cosmochimica Acta)
The ER has moved back from the United States to Hungary with her family and the MSCA let her expand her field of expertise from solid Earth noble gas geochemistry to cosmochemistry by learning and training from the most prestigious European institutions. She studied stellar nucleosynthesis, galactic chemical evolution and the astrophysical importance of meteorites under Lugaro’s supervision, which enabled her to investigate early Solar System processes also from a theoretical approach.
Pető has been actively involved in the Hungarian scientific community, she has given 4 seminar talks at the Bolyai Collegium of Eötvös University (Budapest) and at Debrecen University. She has published an article in „Élet és Tudomány”, a Hungarian science journal, and participated in career advising for women at Eötvös University.
