Assessment of Possible Location Ru-106 Source in Russia in September–October 2017

Abstract

A method for the identification of the source of Ru-106 emergence in the atmosphere in September-October 2017 is considered. The most probable version of Ru-106 inflow to the atmosphere from the ground-based source in the South or Central Urals is substantiated. The backtrajectories of air masses at the height of 500–1500 m from the areas of Ru-106 concentration measurements at the European stations during the corresponding observation period are calculated to identify a possible source of Ru-106 emission to the atmosphere. The regional transport and the propagation of radioactivity in the near zone in case of a hypothetic emission of Ru-106 from the conditional source in the South Urals are simulated to prove the source position correctness. The simulation results are compared with available measurement data on the daily Ru-106 fallout.