All about Lensing: Strong, Weak, and Micro

Strong Lensing

Modeling

• PyAutoLens - Automated Strong Gravitational Lens Modeling
  • From James Nightingale. Based on Adaptive Semi-linear Inversion of Strong Gravitational Lens Imaging and AutoLens: Automated Modeling of a Strong Lens’s Light, Mass and Source
• lenstronomy - Software package for lens model reconstruction of imaging data
  • By Simon Birrer. lenstronomy is a multi-purpose package to model strong gravitational lenses.
  • Based on Lenstronomy: multi-purpose gravitational lens modelling software package
• vislens - Module for modeling gravitational lensing systems in which the data are not images but interferometric visibilities
  • Visilens is a python module for modeling gravitational lensing systems observed by a radio/mm interferometer like ALMA or ATCA.

Weak Lensing

• Some of the tools overlap with the cosmology tools section.
• LensTools - Useful computing tools for Weak Lensing analyses
  • This python add-on will handle basically every operation you will need to perform on Weak Lensing survey data; the distribution includes a range of tools in image analysis, statistical processing and numerical theory predictions and supports multiprocessing using the mpi4py module.
  • Full document can be found here
• TreeCorr
  • By Mark Jarvis. TreeCorr is actually a very general tool for correlation function. Can be used for number counts, cosmic shear, galaxy-galaxy lensing, and other cosmological applications.
• swot - Super W of Theta
  • SWOT is a code to compute two-point statistics for very large data sets, based on “divide and conquer” algorithms. Github repo is here
  • Is a great tool to do galaxy-galaxy lensing.

Shear Measurement

• Galaxy shape measurement with corrections for PSF and other systematics. Different lensing surveys often choose different codes or algorithms to calculate shear.
• GREAT3 - The third GRavitational lEnsing Accuracy Testing challenge
  • GREAT3 is a blind data analysis competition held by the world-wide weak lensing community to test weak lensing measurement algorithms.
  • Details about the challenge can be found in the The Third Gravitational Lensing Accuracy Testing (GREAT3) Challenge Handbook
  • Summary of the challenge can be found in the final GREAT3 conference
  • Public repository for the code can be found on GitHub
• ngmix - Gaussian mixtures and image processing implemented in python
  • By Erin Sheldon. Gaussian mixture models and other code for working with for 2d images, implemented in python.
  • ngmix is adopted by the dark energy survey (DES) as one of the shear measurement tools. Examples of running ngmix on DES MEDS files can be found here
• im3shape - galaxy shape measurement code
  • By Joe Zuntz. Im3shape measures the shapes of galaxies in astronomical survey images, taking into account that they have been distorted by a point-spread function.
  • Im3shape is adopted by the dark energy survey (DES) as one of the shear measurement tools. Please also see Zuntz et al. 2013
• meas_extensions_shapeHSM : HSM shape measurement
  • Used by the LSST Data Management.

Cosmic Shears Analysis

• Weak gravitational lensing CFHTLens analysis
• Public repository for the Monte Python likelihood module for the KiDS-450 cosmic shear correlation functions
  • This repository contains the likelihood module for the KiDS-450 correlation function measurements from Hildebrandt et al. 2017
  • Also the public repository for the Monte Python likelihood module for the KiDS+VIKING-450 (KV450) cosmic shear correlation functions

Galaxy-Galaxy Lensing Tools

• xshear - Measure the tangential shear around a set of lenses
  • By Erin Sheldon. Measure the tangential shear around a set of lenses. This technique is also known as cross-correlation shear, hence the name xshear.
• xpipe - Weak lensing measurement pipeline for wide area surveys
  • By Tamás Norbert Varga. xpipe is a python package created to automate work with measuring and calibrating weak lensing shear and mass profiles in wide area lensing surveys such as DES
• dsigma - Pure-python galaxy-galaxy lensing framework for the HSC survey
  • By Song Huang. dsigma is a pure-python galaxy-galaxy lensing pipeline designed for the Hyper-Suprime Cam survey. It should be flexible enough to work with other surveys after adapting the same data format.

Cluster Lensing

• cluster-lensing - Galaxy Cluster and Weak Lensing Tools
  • By Jes Ford. cluster-lensing is a set of tools to calculate galaxy cluster halo properties and weak lensing shear and magnification profiles.
• Python codes for ongoing cluster analysis of the LSST/DESC cluster group
  • Some of the relevant notebooks can be found here

Weak Lensing Mass Map

• Glimpse - Sparsity based weak lensing mass-mapping tool
  • By [François Lanusse]. Glimpse is a weak lensing mass-mapping tool relying a robust sparsity-based regularisation scheme to recover high resolution convergence from either gravitational shear alone or from a combination of shear and flexion. Please also see Lanusse et al. 2016

Micro Lensing

• Microlensing Source
  • A website that summaries a lot of useful resources and data for microlensing science.
  • It also hosts the Microlensing Data Challenge
  • The data for the challenge can be found on Github
• Microlensing Hack Session at CCA, 2019
  • There is a summary of resources for micro-lensing analysis and a series of interesting micro-lensing projects

Software

• muLAn - gravitational MICROlensing Analysis Software
  • muLAn is an easy-to-use and flexile software to model gravitational microlensing events
• MulensModel - Microlensing Modelling package
  • By Radek Poleski. MulensModel can generate a microlensing light curve for a given set of microlensing parameters, fit that light curve to some data, and return a chi2 value
• LIA - Gravitational microlensing detection algorithm using machine learning
  • LIA is an open-source program for detecting microlensing events in wide-field surveys
• pyLIMA - open source for modeling microlensing events
  • Document for pyLIMA can be found here
• VBBinaryLensing - Microlensing light curve calculation
  • By Valerio Bozza. VBBinaryLensing is a tool for forward modelling of gravitational microlensing events using the advanced contour integration method It supports single and binary lenses.