The Cosmic Background Imager 2
Abstract
We describe an upgrade to the Cosmic Background Imager instrument to increase its surface brightness sensitivity at small angular scales. The upgrade consisted of replacing the thirteen 0.9-m antennas with 1.4-m antennas incorporating a novel combination of design features, which provided excellent sidelobe and spillover performance for low manufacturing cost. Off-the-shelf spun primaries were used, and the secondary mirrors were oversized and shaped relative to a standard Cassegrain in order to provide an optimum compromise between aperture efficiency and low spillover lobes. Low-order distortions in the primary mirrors were compensated for by custom machining of the secondary mirrors. The secondaries were supported on a transparent dielectric foam cone to minimize scattering. The antennas were tested in the complete instrument, and the beam shape and spillover noise contributions were as expected. We demonstrate the performance of the telescope and the inter-calibration with the previous system using observations of the Sunyaev-Zel'dovich effect in the cluster Abell 1689. The enhanced instrument has been used to study the cosmic microwave background, the Sunyaev-Zel'dovich effect and diffuse Galactic emission.
Cite
@article{arxiv.1108.3950,
title = {The Cosmic Background Imager 2},
author = {Angela C. Taylor and Michael E. Jones and James R. Allison and Emmanouil Angelakis and J. Richard Bond and Leonardo Bronfman and Ricardo Bustos and Richard J. Davis and Clive Dickinson and Jamie Leech and Brian S. Mason and Steven T. Myers and Timothy J. Pearson and Anthony C. S. Readhead and Rodrigo Reeves and Martin C. Shepherd and Jonathan L. Sievers},
journal= {arXiv preprint arXiv:1108.3950},
year = {2015}
}
Comments
10 pages,9 colour figures and 1 table; accepted for publication in MNRAS