Cosmogenic radionuclides

© Stephanie Neuhuber, IAG, Universität für Bodenkultur Wien

© Julia Schenk, AlpSenseBench

  • The cosmogenic nuclides 10Be (T1/2 = 1.30 Myr), 26Al (T1/2 = 700 kyr) and 36Cl (T1/2 = 300 kyr) are continuously formed by solar and cosmic radiation in the atmosphere. With their help, natural archives such as ice cores, sediments or water can be dated. If a higher or lower production of the above mentioned nuclides compared to today's rate is detected, this may indicate additional sources of cosmic radiation or changes in the magnetic fields of the earth or our sun in the past. In addition, 10Be, 26Al and 36Cl can be used to measure the duration of exposure to cosmic rays at the surface of a rock. This so-called surface exposure dating can provide information about processes on the Earth's surface and can be used, e.g. to study glacier movements.
  • The newly developed ILIAMS (Ion Laser InterAction Mass Spectrometry) setup at VERA improves the possibility to measure 26Al and 36Cl by laser-assisted isobar separation. By suppressing the isobars 26Mg and 36S by several orders of magnitude, blank values of 26Al/Al = 5×10–16 and 36Cl/Cl = 8×10–16 can be achieved at VERA.

Contact:
Oscar Marchhart, Alexander Wieser
References:
  1. Steier, P., et al. "Comparison of methods for the detection of 10Be with AMS and a new approach based on a silicon nitride foil stack". International Journal of Mass Spectrometry 444 (2019): 116175.
  2. Lachner, J., et al. "36Cl in a new light: AMS measurements assisted by ion-laser interaction". NIMB 456 (2019): 163-168.

Research partners:

  • Stephanie Neuhuber, Institute of Applied Geology (IAG), Universität für Bodenkultur Wien, Austria
  • Zsófia Ruszkicay-Rüdiger, Institute for Geological and Geochemical Research, Hungarian Academy of Sciences (HAS), Hungary
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  • Sohini Bhattacharjee, Geological Remote Sensing - Institute of Geosciences, University Potsdam, Germany