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LSSTDESC / firecrown

DESC Cosmology Likelihood Framework
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Treatment and constrains on systematics parameters #246

Closed elisachisari closed 1 year ago

elisachisari commented 1 year ago

I created a synthetic cosmic shear data vector (5 redshift bins) with some NLA amplitude for alignments. I am analysing it with firecrown with my own Gaussian covariance. I want to see if I recover the right Omega_m and NLA amplitude. I have two questions about this: 1) Is each tracer NLA amplitude assumed to be independent? If yes, is there a way to assume them to be the same? 2) Where can I find the output of the constraints on the NLA amplitude?

tilmantroester commented 1 year ago
  1. If the systematic is defined without specifying sacc_tracer, like in https://github.com/LSSTDESC/firecrown/blob/master/examples/des_y1_3x2pt/des_y1_3x2pt.py#L19, then the parameters are the same for all tracers the systematic is applied to.
  2. The IA parameter is set like this: https://github.com/LSSTDESC/firecrown/blob/master/examples/des_y1_3x2pt/des_y1_3x2pt_values.ini#L25. Since it's being sampled, it will be in the chain output. Derived parameters are supported in principle but not implemented yet in practice.