Current and future CMB experiments such as the Simons Observatory and LiteBIRD aim at measuring extremely faint polarization signals, requiring precise control of instrumental systematic effects. One important source of systematics is the instrumental beam, which can depart significantly from the commonly assumed circularly symmetric shape.
The goal of this 3-month internship is to develop and validate simulations of time-ordered data (TOD) including asymmetric instrumental beams, building on simulation tools currently developed at APC. Starting from simple elliptical Gaussian beams, the student will simulate observations using realistic scanning strategies representative of Simons Observatory and/or LiteBIRD and reconstruct the corresponding CMB maps.
The project will investigate how beam asymmetries propagate into temperature and polarization maps and, depending on progress, quantify effects such as temperature-to-polarization leakage and biases in E- and B-mode signals.
The internship will involve numerical simulations and scientific programming in Python and is suitable for a Master-level student in physics, astrophysics or applied mathematics.
