Rostock 2019 – wissenschaftliches Programm
MS 4.4: Vortrag
Mittwoch, 13. März 2019, 11:15–11:30, U A-Esch 2
Detection of Extraterrestrial 60Fe in Antarctica with AMS — •Dominik Koll1,2, Thomas Faestermann1, Gunther Korschinek1, Silke Merchel3, Jan M. Welch4, and Sepp Kipfstuhl5 — 1Technische Universität München, Germany — 2The Australian National University, Australia — 3Helmholtz-Zentrum Dresden-Rossendorf, Germany — 4TU Wien, Austria — 5Alfred Wegener Institute, Germany
The long-lived radioactive isotope 60Fe with a half-life of 2.6 Myr is mainly produced by stellar nucleosynthesis and ejected into space by core-collapse supernovae. Former investigations by Accelerator Mass Spectrometry (AMS) showed a supernova signal on Earth 1.7-3.2 Myr ago.
Considering an enrichment of the solar neighborhood in long-lived radionuclides by previous supernovae, deposition of 60Fe on Earth could be currently ongoing. To investigate this case, 500 kg of Antarctic snow were analyzed by Accelerator Mass Spectrometry with the 14 MV tandem accelerator and the Gas-filled Analyzing Magnet System (GAMS) at the Maier-Leibnitz-Laboratorium in Garching, Germany.
Indeed, 60Fe was discovered in Antarctic snow and by the measurement of 53Mn, which is dominantly produced by cosmic ray interactions with solar system objects, the origin of these 60Fe atoms could be deduced.