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MA: Fachverband Magnetismus
MA 39: Magnetic Particles / Clusters
MA 39.6: Vortrag
Freitag, 9. September 2022, 10:45–11:00, H47
Drifting inwards in protoplanetary discs: The role of hydrogen on planetesimal formation — •Cynthia Pillich1, Janosch Tasto1, Tabea Bogdan2, Joachim Landers1, Gerhard Wurm2, and Heiko Wende1 — 1Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Lotharstr. 1, 47057 Duisburg, Germany — 2Faculty of Physics, University of Duisburg-Essen, Lotharstr. 1, 47057 Duisburg, Germany
Dust particles in protoplanetary discs, which can be seen as building blocks for planetesimals, are coupled to gas, mostly hydrogen. Due to this coupling, those particles may drift towards the inner part of the disc and are therefore exposed to very high temperatures, allowing for compositional and structural changes.
To simulate the conditions at the early phase of planetary formation, two chondrites were milled to dust and subjected to temperatures up to 1400 K in a hydrogen atmosphere of approximately 1 mbar. The changes in composition were then studied by the means of 57Fe Mössbauer spectroscopy and magnetometry.
Comparing these results to vacuum tempered dust, we observe an influence of the heating atmosphere on compositional changes in the meteorites. At very high temperatures (>1200 K), Fe silicates are mostly reduced to metallic FeNi, altering adhesive properties of protoplanetary dust and therefore the potential for planetesimal growth.
Funding by the DFG (projects WE 2623/19-1 and WU 321/18-1) is gratefully acknowledged.