Physics & Astronomy Colloquium
Dr. Nicholas Galitzki; Simons Observatory Postdoctoral Scholar; Department of Physics; University of California, San Diego
“The Simons Observatory and BLAST-TNG: Probing the beginning of the Universe with precision polarimetry experiments"
Abstract: We are in an exhilarating era in which cosmological models are being tested by cutting-edge instruments that push the boundaries of theoretical predictions and technological innovation. Observations of polarized light from the cosmic microwave background (CMB) will enable us to detect, or constrain, the elusive CMB primordial B-mode signal that is key to understanding the first fraction of a second of our Universe's existence. However, CMB observations are occluded by polarized emission from dust in the galaxy’s interstellar medium that aligns with galactic magnetic fields. The spectral dependence of the polarized dust emission is not well understood, motivating investigations to constrain its properties. I will discuss my work with the Simons Observatory (SO) which will be one of the most sensitive instruments in the world to primordial fluctuations in the CMB signal. I will also give an overview of the BLAST-TNG balloon-borne polarimeter which will allow us to maximize returns on SO by constraining the foreground galactic signals which prevent more sensitive CMB measurements. I will discuss the current status of both these experiments as well as future ground and space-based prospects to improve our understanding of the primordial universe through polarimetry.