Neff and Beam Calibration
Dan writing (input from Tom Crawford, Matthew Hasselfield, Christian Reichardt and Alex van Engelen )
This is an extension of the beam calibration discussion to an earlier post: Update on Neff Forecasts. The main point of this new post is to use the ACT beam eigenmodes directly, rather than a much simpler parameterization of the beam uncertainty. Using the beam eigenmodes will given an unambiguous comparison between the calibration requirements needed to reach σ(Neff) = 0.027 and the calibration levels that have been achieved in ACT (for example).
The forecasts used here use the same parameters as the earlier post, including point-sources and atmosphere.