Astrophysics

Software Packages

To get the best scientific results from the measurement data of our instruments, we develop our own software. With those programmes, we can calculate what spectrum we expect to see for an object and compare it with the real measurement. We make this software available to everyone.

ARCiS

ARCiS is a novel code for the analysis of exoplanet transmission and emission spectra. The aim of the modelling framework is to provide a tool able to link observations to physical models of exoplanet atmospheres. The software is constantly being improved and has been used during the analysis of cutting-edge data from current facilities such as HST and JWST. It will also be used for fitting the data from the upcoming ESA Ariel mission.

Download and install
The easiest way to download and install ARCiS is via GitHub, click here

Help and documentation
The User guide is available at this link.
More information, including data downloads, can be found here.

RADEX

RADEX is a software package to calculate the strengths of molecular and atomic lines from homogeneous gas clouds in the infra-red and microwave band. The user can select a certain molecule and set the temperature, density, column density and line width. Based on these parameters, the program then calculates the position and strength of the emission lines. The program can be run through a web interface or offline on a Linux or Mac computer.

Download and install
The software, written in Fortran, is available for download.
The website also includes installation instructions assuming you have a Fortran compiler installed.

Information and help
The RADEX website  also contains information about how to run the program. More information about the calculations can be found on Zenodo.

Questions or bug reports can be submitted as an issue to our Github issue tracker.

The source code of RADEX is available on Github and Zenodo under an Apache 2.0 license. Everyone is free to use the program. We do request that authors who make use of the RADEX program cite our paper: Van der Tak, F.F.S., et al. 2007 .

SPEX

SPEX is an X-ray spectral analysis software package optimized for the interpretation of high-resolution astrophysical X-ray spectra. The software is especially suited for fitting spectra obtained by current X-ray observatories like XMM-Newton, Chandra, Suzaku, and XRISM. SPEX will be continuously improved to handle spectra from high-resolution X-ray instruments on future missions like NewAthena.

SPEX is open source software and is distributed with a GPLv3 license. The source code is available on Zenodo.

Download and install
SPEX is developed for Linux and Mac systems, but can also run on the Windows subsystem for Linux (WSL) or using a virtual machine. More information about downloading and installing SPEX can be found using this link.

Help and documentation
The SPEX documentation is available on Github. For questions and bug reports, users can submit an issue to the Github repository.

Pyspextools
In addition to the SPEX package, we also have a Python package called pyspextools. This contains tools to convert between files in OGIP format and SPEX format. More information about Pyspextools can be found here:

• Documentation
• Github
• Issues & help
• Zenodo

The pyspextools package is distributed with the Apache 2.0 license.