Observations of atmospheric noise fluctuations with a metre-baseline interferometer in the 13-17 GHz band
This paper describes the atmospheric noise fluctuations that we have observed with the Cosmic Anisotropy Telescope (CAT) at Cambridge. The CAT is a short baseline radio interferometer designed to make observations of primordial anisotropies in the Cosmic Microwave Background Radiation at angular scales between 20 arcminutes and 1 degree. During clear weather the observations are limited by receiver noise, whereas emission and scattering from clouds limits the sensitivity of the instrument during rain and cloudy weather on the very shortest baselines. Fluctuations in the correlated antenna temperature up to 100 mK have been seen, with a typical coherence time of 10 seconds.
Astronomy and Astrophysics
- Pub Date:
- June 1994
- ATMOSPHERIC EFFECTS;
- INSTRUMENTATION: INTERFEROMETERS;
- TECHNIQUES: INTERFEROMETRIC