Optimal filters for the moving lens effect

Understand

We assess the prospects for detecting the moving lens effect using cosmological surveys.

• The bulk motion of cosmological structure induces a small-scale dipolar temperature anisotropy of the cosmic microwave radiation (CMB), centered around halos and oriented along the transverse velocity field.
• We introduce a set of optimal filters for this signal, and forecast that a high significance detection can be made with upcoming experiments.
• We discuss the prospects for reconstructing the bulk transverse velocity field on large scales using matched filters, finding good agreement with previous work using quadratic estimators.