The quasi-optical design of the QUaD telescope

• Published in: Infrared Physics & Technology
• Main Authors: O'Sullivan, C., Cahill, G., Murphy, J. A., Gear, W. K., Harris, J., Ade, P. A. R., Church, S. E., Thompson, K. L., Pryke, C., Bock, J., Bowden, M., Brown, M. L., Carlstrom, J. E., Castro, P. G., Culverhouse, T., Friedman, R. B., Ganga, K., Haynes, V., Hinderks, J. R., Kovak, J., Lange, A. E., Leitch, E. M., Mallie, O. E., Melhuish, S. J., Orlando, A., Piccirillo, L., Pisano, G., Rajguru, N., Rusholme, B. A., Schwarz, R., Taylor, A. N., Wu, E. Y. S., Zemcov, M.
• Other Authors: APC - Cosmologie, AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), QUaD
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2008
• Subjects: Optical system design; Antennas: theory; components and accessories; Radio; microwave; Background radiations; [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO]; [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO]; [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph]; South pole
• Online Access: https://hal.in2p3.fr/in2p3-00186031; https://doi.org/10.1016/J.INFRARED.2007.10.001

We describe the optical design and performance of 'QUEST and DASI' or 'QUaD', a ground-based high-resolution experiment designed to measure the polarisation properties of the cosmic microwave background radiation. QUaD uses bolometric detectors at 100 and 150 GHz on a 2.6 m Cassegrain telescope. The QUaD optics are designed to minimise systematic effects as well as to maximise sensitivity, and we report here on the comprehensive quasi-optical analysis used to achieve this design. We also present initial optical performance measurements achieved in operation, and discuss changes made to the optics to overcome some errors in the mechanical construction of the primary mirror. The QUaD experiment is now fully operational and taking world-leading data at the South Pole.