Estimates of delensing efficiency
Delensing with a dedicated telescope at the pole - AL=0.13
This was the assumption made for the CDT report. At the time of writing no new reference configuration is available. The forecast for the delensing efficiency for the CDT configuration was AL=0.13.
Delensing with the large area telescopes from Chile
Here I will rely on the recent configuration denoted 'Survey Performance Expectation 01' in the posting Survey Performance Expectations. The post does not contain all required information (e.g. lknee and the exponent for the 1/f contribution). Based on the corresponding pdf, I assume that for polarization lknee=800 and an exponent of -1.5. This leads to the following noise curves
Delensing with the large area telescopes from Chile and a dedicated LAT for delensing
Here I will assume an additional telescope dedicated to delensing with the same characteristics as the LATs described in 'Survey Performance Expectation 01' and observing the Chile mask shown in the posting Sky masks for simulations II