Astrophysics Source Code Library

Making codes discoverable since 1999

Welcome to the ASCL

The Astrophysics Source Code Library (ASCL) is a free online registry for source codes of interest to astronomers and astrophysicists and lists codes that have been used in research that has appeared in, or been submitted to, peer-reviewed publications. The ASCL is indexed by the SAO/NASA Astrophysics Data System (ADS) and Web of Science and is citable by using the unique ascl ID assigned to each code. The ascl ID can be used to link to the code entry by prefacing the number with (i.e.,

Most Recently Added Codes

2019 Jan 16

[submitted] Galaxia_wrap

Galaxia_wrap is a python wrap around the popular Galaxia tool that can be used to generate mock stellar surveys using a built-in Galaxy model or directly from n-body data.
It is shown how a magnitude limited survey can be constructed. The n-body functionality is also demonstrated and one application shows how the age distribution of a specific stellar tracer population can be inferred, which could be useful for creating mock data.

2019 Jan 14

[submitted] SEDobs: Observational Spectral energy distribution simulation

SEDobs is a program that aims at using state of the art theoretical gelaxy SED (spectral energy distribution) to create simulated observation of distant galaxies. It used BC03 and M05 theoretical models and allows the user to configure the simulated observation that are needed. For a given simulated galaxy, the user is able to simulate multi-spectral and multi-photometric observations.

[submitted] Photon: Python tool for data plotting

Photon is a GUI created to make simple 1D plot in python. It uses mainly matplotlib and PyQt5 and it has been build in the spirit of being fully customizable. You can change fontstyle, fontsize, fontcolors, linewidth of the axes, thickness, etc…and see the changes directly in the plot. Once a customization is created, you can save it into a configuration file and reload it later when you open photon again. This allows you to keep the same customization for different plot. The main tool is a graphical user interface and it is started using a command line interface.

[submitted] unwise_psf: PSF Models for unWISE Coadds

The unwise_psf Python module renders point spread function (PSF) models appropriate for use in modeling of unWISE coadd images. unwise_psf translates highly detailed single-exposure WISE PSF models in detector coordinates to the corresponding pixelized PSF models in coadd space, accounting for subtleties including the WISE scan direction and its considerable variation near the ecliptic poles. Applications of the unwise_psf module include performing forced photometry on unWISE coadds, constructing WISE-selected source catalogs based on unWISE coadds and masking unWISE coadd regions contaminated by bright stars.

2019 Jan 10

[submitted] Core Cosmology Library

The Core Cosmology Library (CCL) provides routines to compute basic cosmological observables to a high degree of accuracy, which have been verified with an extensive suite of validation tests. Predictions are provided for many cosmological quantities, including distances, angular power spectra, correlation functions, halo bias and the halo mass function through state-of-the-art modeling prescriptions available in the literature. Fiducial specifications for the expected galaxy distributions for the Large Synoptic Survey Telescope (LSST) are also included, together with the capability of computing redshift distributions for a user-defined photometric redshift model. A rigorous validation procedure, based on comparisons between CCL and independent software packages, allows us to establish a well-defined numerical accuracy for each predicted quantity. As a result, predictions for correlation functions of galaxy clustering, galaxy-galaxy lensing and cosmic shear are demonstrated to be within a fraction of the expected statistical uncertainty of the observables for the models and in the range of scales of interest to LSST. CCL is an open source software package written in C, with a python interface and publicly available at

2019 Jan 02

[submitted] OCFit - Python package for fitting of O-C diagrams.

There are many different methods for fitting and analysing O-C diagrams. We present a new fitting tool for analysing O-C diagrams. Our method is based on Genetic Algorithms and Markov chain Monte Carlo. Monte Carlo method is used also to a very good estimation of errors of the parameters. Unlike many others fitting routine, our method does not need any initial values of fitted parameters. Fitting using presented software is quite simple thanks to a very intuitive graphic user interface. Currently, nine most common models of periodic O-C changes are included in this software.

2018 Dec 31

[ascl:1812.018] OctApps: Octave functions for continuous gravitational-wave data analysis

The OctApps library provides various functions, written in Octave, for performing searches for the weak signatures of continuous gravitational waves from rapidly-rotating neutron stars amidst the instrumental noise of the LIGO and Virgo detectors.

[ascl:1812.017] psrqpy: Python module to query the ATNF Pulsar Catalogue

psrqpy directly queries the Australia Telescope National Facility (ATNF) Pulsar Catalogue by downloading and parsing the full catalog database, which is cached and can be reused. The module assists astronomers who want access to the latest pulsar information via a script rather than through the standard web interface.

[ascl:1812.016] Juliet: Transiting and non-transiting exoplanetary systems modelling tool

Juliet essentially serves as a wrapper of other tools, including Batman (ascl:1510.002), George (ascl:1511.015), Dynesty (ascl:1809.013) and AstroPy (ascl:1304.002), to analyze and model transits, radial-velocities, or both from multiple instruments at the same time. Using nested sampling algorithms, it performs a thorough sampling of the parameter space and a model comparison via Bayesian evidences. Juliet also fits transiting and non-transiting multi-planetary systems, and Gaussian Processes (GPs) which might share hyperparameters between the photometry and radial-velocities simultaneously (e.g., stellar rotation periods).

[ascl:1812.015] AUTOSPEC: Automated Spectral Extraction Software for integral field unit data cubes

AUTOSPEC provides fast, automated extraction of high quality 1D spectra from astronomical datacubes with minimal user effort. AutoSpec takes an integral field unit (IFU) datacube and a simple parameter file in order to extract a 1D spectra for each object in a supplied catalogue. A custom designed cross-correlation algorithm improves signal to noise as well as isolates sources from neighboring contaminants.