The Askaryan Radio Array (ARA) at the South Pole is designed to detect the radio signals produced by ultra high-energy cosmic neutrino interactions in the ice. There are 5 independent ARA stations, one of which (ARA5) includes a low-threshold phased array trigger string. The Data Acquisition System in all ARA stations is equipped with the Ice Ray Sampler second generation (IRS2) chip, a custom-made, application-specific integrated circuit (ASIC) for high-speed sampling and digitisation. In this contribution, we describe the methodology used to calibrate the IRS2 chip and the geometry namely the relative timing between antennas and their geometrical positions, for ARA stations 4 and 5. Our calibration allows for proper timing correlations between incoming signals, which is crucial for radio vertex reconstruction and thus detection of ultra high-energy neutrinos. With this methodology, we achieve a signal timing precision on a sub-nanosecond level and an antenna position precision within 10 cm.
Askaryan Radio Array;ARA;Calibration;Digitisation;IRS2 chip; ASIC;Station Geometry;Timing precision;Antenna Positioning;Data Acquisition System;Ultrahigh energy;Neutrino detection
|other Collaboration||Askaryan Radio Array (ARA) Collaboration|
|Collaboration||other (fill field below)|
|Subcategory||Experimental Methods & Instrumentation|