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Radio-glaciological parameters from Moores Bay, in the Ross Ice Shelf, have been measured. The thickness of the ice shelf in Moores Bay was measured from reflection times of radio-frequency pulses propagating vertically through the shelf and reflecti ng from the ocean, and is found to be $576pm8$ m. Introducing a baseline of 543$pm$7 m between radio transmitter and receiver allowed the computation of the basal reflection coefficient, $R$, separately from englacial loss. The depth-averaged attenuation length of the ice column, $<L >$ is shown to depend linearly on frequency. The best fit (95% confidence level) is $<L( u) >= (460pm20)-(180pm40) u$ m (20 dB/km), for the frequencies $ u=$[0.100-0.850] GHz, assuming no reflection loss. The mean electric-field reflection coefficient is $sqrt{R}=0.82pm0.07$ (-1.7 dB reflection loss) across [0.100-0.850] GHz, and is used to correct the attenuation length. Finally, the reflected power rotated into the orthogonal antenna polarization is less than 5% below 0.400 GHz, compatible with air propagation. The results imply that Moores Bay serves as an appropriate medium for the ARIANNA high energy neutrino detector.
The Antarctic Ross Ice Shelf Antenna Neutrino Array (ARIANNA) is a high-energy neutrino detector designed to record the Askaryan electric field signature of cosmogenic neutrino interactions in ice. To understand the inherent radio-frequency (RF) neut rino signature, the time-domain response of the ARIANNA RF receiver must be measured. ARIANNA uses Create CLP5130-2N log-periodic dipole arrays (LPDAs). The associated effective height operator converts incident electric fields to voltage waveforms at the LDPA terminals. The effective height versus time and incident angle was measured, along with the associated response of the ARIANNA RF amplifier. The results are verified by correlating to field measurements in air and ice, using oscilloscopes. Finally, theoretical models for the Askaryan electric field are combined with the detector response to predict the neutrino signature.
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