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            <gmx:Anchor xlink:href="https://inspire.ec.europa.eu/theme/ac" xlink:actuate="onRequest">Atmospheric conditions</gmx:Anchor>
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                    <gco:Date>2021-01-06</gco:Date>
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The data used in this study were collected by the Burst Detector Dosimeter IIR (BDD-IIR) on board the US GPS satellite NS41. The data is publicly available from  http://www.ngdc.noaa.gov/stp/space-weather/satellite-data/satellite-systems/gps/data/ns41. Full details of the subsequent analysis are given in Meredith et al. (2025).
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BDD-IIR is a multi-purpose silicon detector system. It features 8 individual channels of a "shield/filter/sensor" design that permits the detector to sample roughly half the celestial sphere while at the same time shielding the silicon sensor elements from most of the incident particle flux.
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