Decide on a pixelization for the analysis

[Mathew S. Madhavacheril]

Healpix:

• systematics maps in DES are in healpix
• equal area means it's easier to define a galaxy overdensity
• requires repixelizing ACT maps, but should be doable with an alm-based transform that preserves power
• deprojection and mode coupling extensively tested here

CAR:

• CMB and lensing maps are natively produced here
• repixelizing systematics maps to CAR might introduce a transfer function (can't use alm-based due to sharp edges, need to interpolate)
• curved sky mode coupling and deprojection are experimental

I'm leaning towards healpix.