ACT Data Products - Beam Radial Profile and Beam Transforms
These files contain the radial profile and beam transforms of the ACT beam, suitable for point source use with ACT 150, 220, and 280 GHz maps from 2008 to 2010. The planet beams are described in Hasselfield, Moodley et al. (2013), and the specific modifications for point sources are described in Vargas et al. (2023).
The real space beam is the azimuthally averaged point spread function, normalized to 1 at Θ=0, and includes the effects of pointing variance and the pixel aperture. The first column of the file is the angle theta in degrees, and the second column is the beam amplitude.
The beam transform is the harmonic transform (on the sphere) of the azimuthally averaged beam. The Fourier space window function is obtained by squaring the beam transform. The first column of the file is the angular frequency, ell, and the second column is the beam transform normalized to 1 at ℓ=0.
The solid angle of the point spread functions in the ACT maps varies for each season and array, as described in Hasselfield, Moodley et al. (2013). The specific solid angle of these beams is included in Table 3 of Vargas et al. (2023).