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  • The C-Band All-Sky Survey (...
    King, O. G; Jones, Michael E; Blackhurst, E. J; Copley, C; Davis, R. J; Dickinson, C; Holler, C. M; Irfan, M. O; John, J. J; Leahy, J. P; Leech, J; Muchovej, S. J. C; Pearson, T. J; Stevenson, M. A; Taylor, Angela C

    Monthly notices of the Royal Astronomical Society, 03/2014, Letnik: 438, Številka: 3
    Journal Article

    The C-Band All-Sky Survey is a project to map the full sky in total intensity and linear polarization at 5 GHz. The northern component of the survey uses a broad-band single-frequency analogue receiver fitted to a 6.1-m telescope at the Owens Valley Radio Observatory in California, USA. The receiver architecture combines a continuous-comparison radiometer and a correlation polarimeter in a single receiver for stable simultaneous measurement of both total intensity and linear polarization, using custom-designed analogue receiver components. The continuous-comparison radiometer measures the temperature difference between the sky and temperature-stabilized cold electrical reference loads. A cryogenic front-end is used to minimize receiver noise, with a system temperature of 30 K in both linear polarization and total intensity. Custom cryogenic notch filters are used to counteract man-made radio frequency interference. The radiometer 1/f noise is dominated by atmospheric fluctuations, while the polarimeter achieves a 1/f noise knee frequency of 10 mHz, similar to the telescope azimuthal scan frequency.