Polarimeter Receiver Prototyping and Testing for the South Pole Telescope Upgrade

Experimental evidence has so far been supportive for the inflationary Big Bang model of cosmology, while imposing other mysteries, such as the fact that dark matter and dark energy actually consist of 95 % of the observable universe. The forthcoming upgrade of the South Pole Telescope, planned for 2...

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Bibliographic Details
Main Author: Constantinos Melachrinos
Other Authors: The Pennsylvania State University CiteSeerX Archives
Format: Text
Language:English
Published: 2009
Subjects:
Online Access:http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.216.4162
http://hep.uchicago.edu/cdf/frisch/p335/final_melachrinos.pdf
Description
Summary:Experimental evidence has so far been supportive for the inflationary Big Bang model of cosmology, while imposing other mysteries, such as the fact that dark matter and dark energy actually consist of 95 % of the observable universe. The forthcoming upgrade of the South Pole Telescope, planned for 2010, will include a polarimeter with increased sensitivity compared to the current system. Measurements of the CMB polarization anisotropy to a high accuracy will describe the angular power spectrum of the B-mode polarization, which will help unravel some of the mysteries. We prototype and test a digital frequency multiplexed readout system for the SPT upgrade. The digital system has three advantages: it is able to reconstruct both the amplitude and the phase of the multiplexed signals, it has improved low frequency noise and increased multiplexing depth. We implement a prototype readout system and use it to characterize prototype detectors for the polarimeter. The system calibration and optical coupling measurements agree with expected results. The discrepancies are explained with systematic uncertainties. The noise spectrum is improved over the previous system, but further study is needed to minimize external factors and obtain the noise equivalent power. The readout system is robust and well-characterized to make measurements of detector parameters. 1