Measurement of environmental radiation and analysis of microdosimetric spectra of cosmic rays during the 35th expedition to Indian station Bharati, Antarctica

Abstract

Tissue equivalent proportional counter (TEPC) model HAWK FWAD-3 was used for the evaluation of absorbed dose, dose equivalent rate (ḢTEPC) and microdosimetric spectra measured (i) in the mixed radiation fields formed mainly by cosmic rays onboard aircraft during the flights between Mumbai and the Indian station Bharati (Progress air base), two polar flights at Antarctica, and (ii)ground level environmental radiation field at locations situated in three continents, namely Antarctica, Africa and Asia with different latitudes. The study also includes evaluation of absorbed dose rate, dose equivalent rate of cosmic rays and terrestrial radiation using active detectors namely RADEYE-G and BERTHOLD Rem counter. An effort was made to compare the measured dose equivalent rate by TEPC for the commercial flight routes to Antarctica with the values calculated by the software code EPCARD and a good agreement was observed. The 35th expedition to Bharati, Antarctica showed higher values of dose equivalent at the pole (Larsemann Hills region, 69°24′37.60″S, 76°11′01.70″E) than the world average for an evaluation period of six months during summer.