Planar Orthomode Transducers for Feedhorn-coupled TES Polarimeters.

Authors :: McMahon, J.
Appel, J. W.
Austermann, J. E.
Beall, J. A.
Becker, D.
Benson, B. A.
Bleem, L. E.
Britton, J.
Chang, C. L.
Carlstrom, J. E.
Cho, H. M.
Crites, A. T.
Essinger-Hileman, T.
Everett, W.
Halverson, N. W.
Henning, J. W.
Hilton, G. C.
Irwin, K. D.
Mehl, J.
Meyer, S. S.
Source :: AIP Conference Proceedings. 12/16/2009, Vol. 1185 Issue 1, p490-493. 4p.
Publication Year :: 2009
Abstract: We present simulations and discuss measurements of a planar orthomode transducer (OMT) being developed for use with bolometric detectors in observations of the polarization of the cosmic microwave background (CMB). This OMT couples radiation from a circular waveguide onto microstrip where it is filtered and then detected. A corrugated feed horn defines the optical beam. Simulations suggest this OMT achieves a coupling efficiency of greater than 96% with cross-polarization below 1% over 30% bandwidth. [ABSTRACT FROM AUTHOR]