BaR-SPOrt: the instrument to be accommodated at Dome C

Abstract

The BaR-SPOrt (Balloon-Borne Radiometers for SkyPolarizationObservations) experiment, a program of the AgenziaSpazialeItaliana (ASI) co-funded by PNRA (Progetto Nazionale di Ricerca inAntartide) was originally designed as a payload for long durationballoons flights. The changing scenario, both scientific andstrategic, has led us to propose it for the starting wintercampaign of at the Concordia Base. Here the instrument and thefeatures making it suitable to operate at Dome-C are described.After the initial setup, BaR-SPOrt should not require any kind ofroutine intervention by a dedicated base staff. The experimentwill just need electrical power (less than 2 kW) and a suitableaccommodation on the field. It can be fully monitored andcontrolled, including the data acquisition, through its owntelemetry/telecommand link using IRIDIUM modems. Both the receiverand the critical electronics are housed inside atemperature-controlled vacuum chamber, providing the properlystabilized environment. The cold part of the radiometer employs aclosed loop mechanical cryo-cooler that provides temperatures <70 ± 0.1 K with low power consumption (<200 W).