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Overview

dsigma is an easy-to-use python package for measuring gravitational galaxy-galaxy lensing. Using a lensing catalog, it estimates excess surface density around a population of lenses, such as galaxies in the Sloan Digital Sky Survey or the Baryon Oscillation Spectroscopic Survey. It has a broadly applicable API and can utilize data from the Dark Energy Survey (DES), the Kilo-Degree Survey (KiDS), and the Hyper-Suprime Cam (HSC) lensing surveys, among others. With core computations written in C, dsigma is very fast. Additionally, dsigma provides out-of-the-box support for estimating covariances with jackknife resampling and calculating various summary statistics. Below is a plot showing the excess surface density around galaxies in the CMASS sample calculated with dsigma. Below is a plot showing the excess surface density around galaxies in the CMASS sample calculated with dsigma.

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Authors

  • Johannes Lange

  • Song Huang

Attribution

dsigma is listed in the Astronomy Source Code Library. If you find the code useful in your research, please cite Lange & Huang (2022).

License

dsigma is licensed under the MIT License.

Getting Started