Elsevier

New Astronomy Reviews

Volume 47, Issues 11–12, December 2003, Pages 1083-1089
New Astronomy Reviews

QUEST on DASI: a South Pole CMB polarization experiment

https://doi.org/10.1016/j.newar.2003.09.033Get rights and content

Abstract

QUEST on DASI is a ground-based, high-sensitivity, high-resolution (ℓmax∼2500) experiment designed to map CMB polarization at 100 and 150 GHz and to measure the power spectra from E-modes, B-modes from lensing of the CMB, and B-modes from primordial gravitational waves. The experiment comprises a 2.6 m Cassegrain optical system, equipped with an array of 62 polarization-sensitive bolometers (PSBs), located at the South Pole. The instrument is designed to minimize systematic effects; features include differencing of pairs of orthogonal PSBs within a single feed, a rotatable achromatic waveplate, and axisymmetric rotatable optics. In addition the South Pole location allows both repeatable and highly controlled observations. QUEST on DASI will commence operation in early 2005.

Section snippets

The QUEST on DASI experiment

We are building a ground-based polarization experiment called QUEST (Q U Extra-galactic Survey Telescope) on DASI (the Degree Angular Scale Interferometer). In late 2004, the existing DASI receivers and feedhorns will be removed and replaced with a bolometric receiver mounted on a 2.6 m Cassegrain telescope. First light is expected in early 2005. QUEST on DASI is intended not only to provide detailed measurements of the E-mode power spectrum, but also to measure the B-mode power spectrum from

Instrument specifications and design philosophy

The specifications of QUEST on DASI are listed in Table 1, Table 2. They include a large field of view and a large number of pixels to achieve the high instantaneous sensitivity required to permit fast mapping of large areas of sky (the instantaneous sensitivity at 150 GHz is similar to that expected for the Planck satellite). The angular resolution of the experiment has been chosen to give a cutoff in ℓ-space of about 2500, in order to span the expected peak in both the E-mode signal, and the B

Observational strategy and predicted results

We expect to operate QUEST on DASI for at least two years beginning in early 2005. Observations will be continuous over the polar winter. The experiment has been designed (based on the experience of DASI and re-using much of the existing control system) for both remote and automatic operation, and will only require the attention of one full-time person on site over the Polar winter.

At the South Pole the sky only moves in azimuth relative to the ground and so the same region can be observed

Acknowledgements

This material is based upon work supported by the National Science Foundation under Grants 9987360 and 0096778, by the Particle Physics and Astronomy Research Council in the UK, and by the Irish Research Council for Science, Engineering and Technology.

References (9)

  • C.L. Bennett

    ApJ

    (2003)
  • Bowden, M., et al., 2003. MNRAS,...
  • A. Benoît

    A&A

    (2003)
  • Farese, P.C., et al., 2003. These Proceedings. Available from...
There are more references available in the full text version of this article.

Cited by (31)

  • The quasi-optical design of the QUaD telescope

    2008, Infrared Physics and Technology
    Citation Excerpt :

    By breaking degeneracies inherent in the temperature spectrum alone, accurate polarisation measurements by the latest generation of CMB experiments will lead to tighter constraints on cosmological parameters describing the density, composition, and expansion rate of the universe [2]. The Q and U extragalactic survey telescope (QUEST) at the degree angular scale interferometer (DASI) telescope [3] (the combination now called QUaD) is a ground-based experiment designed to produce the first high-resolution high signal-to-noise map of the CMB E-mode polarisation. It is also expected to make an important contribution to B-mode surveys and when combined with the four-year WMAP data will improve constraints on many cosmological parameters [4].

  • Massive neutrinos and cosmology

    2006, Physics Reports
View all citing articles on Scopus
View full text