Stockholm Group: The SO team at Stockholm University, Sweden. We are developing a research program that combines advanced time-domain beam convolution techniques with state-of-the-art optical and radio-frequency (RF) simulation capabilities. As part of this effort, we have developed the ability to quickly generate large ensembles of physical optics beam models that we then input to our beam convolution code to simulate spurious signals generated when a non-ideal beam scans the sky. Recent progress within this overall program is allowing us to more accurately capture effects caused by non-ideal HWP performance and both ground screen and forebaffle diffraction effects. This will help us predict and look for systematic effects during initial calibration and early data analysis. From top left, clockwise: Alexandre Adler, Jon Gudmundsson, Nadia Dachlythra, Alexeï Molin.