emilyst / LensIt

Geek Repo:Geek Repo

Github PK Tool:Github PK Tool

Lensit

This is a set of python tools dedicated to CMB lensing and CMB delensing, by Julien Carron.

Main features are:

  • Maximum a posterior estimation of CMB lensing deflection maps from temperature and/or polarization maps.
    (See https://arxiv.org/abs/1704.08230 by J.Carron and A. Lewis)
  • Wiener filtering of masked CMB data and allowing for inhomogenous noise, including lensing deflections, using a multigrid preconditioner.
    (Described in the same reference)
  • Fast and accurate simulation libraries for lensed CMB skies, and standard quadratic estimator lensing reconstruction tools.
    (See https://arxiv.org/abs/1611.01446 by J. Peloton et al.)
  • CMB internal delensing tools, including internal delensing biases calculation for temperature and/or polarization maps.
    (See https://arxiv.org/abs/1701.01712 by J. Carron, A. Lewis and A. Challinor)

Several parts were directly adapted from or inspired by qcinv (https://github.com/dhanson/qcinv) and quicklens (https://github.com/dhanson/quicklens) by Duncan Hanson, many thanks to him.

Many parts use the flat-sky approximation, with likely extension to curved-sky in a near future.
To use the GPU implementation of some of the routines, you will need pyCUDA. (https://mathema.tician.de/software/pycuda)

An ipython notebook 'demo_basics.ipynb' covers the simple aspects of building simulation librairies.

(New Sept. 2018) The notebook 'demo_lensit.ipynb' shows an example of iterative lensing map reconstruction for a configuration roughly in line with CMB Stage IV specifications.

Other example and tests scripts might follow, or you may just write to me.

alt text

About


Languages

Language:Jupyter Notebook 69.4%Language:Python 27.5%Language:C 1.6%Language:Fortran 1.2%Language:C++ 0.2%