Simons Observatory:UK technology development and demonstration

During the last three decades, measurements of the Cosmic Microwave Background (CMB) have been the driving force in establishing the standard cosmological model. UK scientists have played a pivotal role, particularly in recent times with major roles in ESA's Planck mission. These advances have been hugely important but the CMB's greatest contributions to fundamental physics could well be yet to come. The primary science goals of future CMB experiments include (i) the search for curl or ``B-mode" fluctuations on large angular scales in the CMB polarisation field, a tell-tale signature of primordial gravitational waves from inflation, (ii) to search for new light relic particles beyond the Standard Model through their imprint on the CMB fluctuations on small angular scales, (iii) to use measurements of the gravitational lensing and Sunyaev-Zel'dovich (SZ) effects in the CMB to constrain the sum of the neutrino masses and (iv) to help understand the observed accelerated expansion of the Universe using the low-redshift probes of CMB lensing and SZ measurements. The high sensitivity and high angular resolution of future experiments will also facilitate a wide range of additional frontier science ranging from studies of the reionisation era to searching for additional solar system objects.

Simons Observatory (SO) is a US-led international project to construct a group of CMB telescopes in the Atacama Desert in northern Chile. It has been designed to address these new science challenges, and is due to begin operations in 2023.

This project is concerned with the design, development and validation of state-of-the-art Kinetic Inductance Detectors and their associated warm readout system for deployment on SO's large aperture telescope (LAT).