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 flexible API and can utilize data from, DECADE, 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.

_images/plot.png — Galaxy-galaxy lensing amplitude around galaxies in the BOSS LOWZ sample calculated with `dsigma`.¶

Authors¶

Johannes Lange
Song Huang

Documentation was edited with the assistance of Claude Sonnet 4.6.

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.