Assessment of Mn deposition on Earth via accelerator mass spectrometry.

The Mn flux onto Earth is a quantity relevant for different extraterrestrial and astrophysical questions. It is a proxy for related fluxes, such as supernova-produced material or interplanetary dust particles. In this work, we performed a first attempt to assess the Mn flux by measuring the Mn/Be isotopic ratio in a 1400 L sample of molten Antarctic snow by AMS (Accelerator Mass Spectrometry). Using the Be production rate in the atmosphere, an upper limit of 5.5 × 10 atoms cm yr was estimated for the deposition of extraterrestrial Mn. This result is compatible with one of the two discrepant values existing in the literature.