Development of Azimuthal Scanning for The Simons Observatory Test Small Aperture Telescope

Abstract

The Simons Observatory project plans to deploy a series of four telescopes to the Atacama Desert in Chile. The Test Small Aperture Telescope (TSAT) at Princeton, which is the focus of this project, is one of four small aperture telescopes (SATs) that, along with one large aperture telescope (LAT), will search for minute primordial fluctuations in the Cosmic Microwave Background (CMB). Specifically, TSAT is designed to search for the signal of primordial gravitational waves in the large-angular scale polarization of the CMB. An important element of the experiment concerns the scan strategy of TSAT as it observes the sky and the interaction of the scanning mechanism with detectors in the cryostat. In this thesis, I give an overview of the SO experiment and describe recent progress made on the development of TSAT. I also describe an azimuthal scanning mechanism (servo drive, motor, encodor, and emergency failsafe) to be coupled to the base of TSAT and explain how azimuthally scanning the telescope affects the accuracy of the readout of other internal components.