Dynamic behavior of ultra stable oscillators under irradiation at low dose rate

The radiation induced shifts of frequency observed under fragmented and continuous exposures at low dose rate (Low Earth's Orbit-LEO-and Geostationary Earth's Orbit-GEO-simulations) on Ultra Stable Oscillators equipped with electrodeless (BVA) and self sustained (QAS) crystals, with swept and unswept quartz are presented. The drifts appear as the sum of two components; the first saturating and annealing rapidly, the second, seen during continuous exposure, probably varies during the few months after the end of the irradiation.<
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