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arXiv · 2506.03900

L-BASS: A project to produce an absolutely calibrated 1.4 GHz sky map. II -- Technical Description of the System

D. P. Zerafa·P. N. Wilkinson·C. J. Radcliffe·J. P. Leahy·I. W. A. Browne·P. J. Black
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Abstract

L-BASS is an instrument designed to make radiometric temperature measurements of the sky with an absolute accuracy of better than 0.1 K at 1.4 GHz. This will be achieved in two steps: first by measuring the sky temperature relative to that of the North Celestial Pole, using two horn-based antennas, and second with the sky antenna replaced with a calibrated cryogenic load to measure the absolute brightness temperature of the North Celesial Pole. Here we describe the design of the L-BASS two-antenna system and report on laboratory measurements to establish its performance at component and sub-system level.

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D. P. Zerafa, P. N. Wilkinson, C. J. Radcliffe, J. P. Leahy, I. W. A. Browne, P. J. Black. 2025-06-04. L-BASS: A project to produce an absolutely calibrated 1.4 GHz sky map. II -- Technical Description of the System. https://doi.org/10.1093/rasti%2Frzaf022

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