# R-forecasting: delensing discussion

Guide for discussion (copied from Clem's email):

1) Enhance the Fisher matrix code which Victor has been using for band selection optimization to deal with lensing more realistically. No actual maps will be involved.

2) Take the high-res maps already being generated for S4 "data challenges" and reconstruct phi from them. These can then be used to generate a lensing template for use when these maps are being re-analyzed "BK style", and presumably in other styles of analysis.

**Action items from S4 delensing and r call:**

**Fisher forecasting:**

***** Victor, Colin H., Mat, DW, Blake, Neelima

- will iterate on values to try for numbers of detectors for high-res and low-res surveys;

- will also iterate on which sky fractions to try;

- Colin H. will make foreground-cleaned Nl^BB and Nl^EE curves and pass them to Mat/DW;

- Mat/DW will generate AL curves and delensing efficiency curves and send them to Victor

- Victor will run through the range of delensing curves for each of his detector count models and produce a grid from which we can identify which combinations reach the S4 sigma(r) target, and of those, which has the smallest detector usage; he may put the fisher part of his code on github

**Map-level explorations:**

***** Alex, Colin B, Clem, Raphael - put high-res foreground sims on NERSC for all to use

***** Kimmy, Yuuki, Alessandro, Kyle, Tom, Alex, DW, Julian C., Blake - run high-res foreground sims through delensing code to explore bias on r

***** Kimmy, Yuuki, Alessandro, Kyle, Tom - explore effects of missing modes, edge effects, and small patches

***** Julian C., Blake - implement map-based maximum likelihood code