Bibcode
Gallegos, J. E.; Macías-Pérez, J. F.; Gutiérrez, C. M.; Rebolo, R.; Watson, R. A.; Hoyland, R. J.; Fernández-Cerezo, S.
Bibliographical reference
Monthly Notices of the Royal Astronomical Society, Volume 327, Issue 4, pp. 1178-1186.
Advertised on:
11
2001
Citations
11
Refereed citations
10
Description
We describe the first instrument of a cosmic microwave background
experiment for mapping cosmological structures on medium angular scales
(the COSMOSOMAS experiment) and diffuse Galactic emission. The
instrument is located at Teide Observatory (Tenerife) and is based on a
circular scanning sky strategy. It consists of a 1-Hz spinning flat
mirror directing the sky radiation into a 1.8-m off-axis paraboloidal
antenna, which focuses it on to a cryogenically cooled HEMT-based
receiver operating in the frequency range 12-18GHz. The signal is split
by a set of three filters, allowing simultaneous observations at 13, 15
and 17GHz, each with a 1-GHz bandpass. A 1°-5° resolution sky
map complete in right ascension and covering 20° in declination is
obtained each day at these frequencies. The observations presented here
correspond to the first months of operation, which have provided a map
of 9000deg2 on the sky centred at Dec.=+31° with
sensitivities of 140, 150 and 250μK per beam area in the channels at
13, 15 and 17GHz, respectively. We discuss the design and performance of
the instrument, the atmospheric effects, the reliability of the data
obtained and prospects of achieving a sensitivity of 30μK per beam in
2 years of operation.