This letter contains three announcements:

  • Publication of the BornAgain reference paper in J. Appl. Cryst.
  • Changes in development team
  • Release 1.17

Reference paper

A comprehensive description of BornAgain has been published as an open-access article in the Journal of Applied Crystallography:

G. Pospelov, W. Van Herck, J. Burle, J. M. Carmona Loaiza, C. Durniak, J. M. Fisher, M. Ganeva, D. Yurov and J. Wuttke, BornAgain: software for simulating and fitting grazing-incidence small-angle scattering. J. Appl. Cryst. 53, 262-276 (2020),

This is intended to be the canonical reference for many years to come; please cite this article whenever refering to the BornAgain project. Additionally, please continue to document the use of a specific software version by an appropriate citation as suggested [here](}}< relref “m/howto/cite” >}}).

Change in development team

Walter Van Herck and Dmitry Yurov have left our group to reorient themselves geographically or/and career-wise. Walter has been one of the two lead developers since the start of the project in 2012. Dmitry joined in 2017 with funding from the European Spallation Source. We are very grateful to Walter and Dmitry for their lasting contributions to BornAgain.

In the meantime two new research software engineers have joined the team, Alexander Schober and Randolf Beerwerth. Alexander has been with the MLZ Scientific Computing Group since 2018, and has so far worked on two data reduction projects. He is now supporting Gennady in a deep overhaul of the GUI, in view of its generalization to reflectometry. Randolf has been with us since February 2020; he is currently working on the reflectometry core and on polarization support.

Release 1.17.0

Today, BornAgain 1.17.0 has been released.

New Core functionality includes the Nevot-Croce roughness model, support for switching between roughness models and reflectometry engines, and a few new form factors (cantellated cubes, rectangular ripples). The API has changed for ripples, as described in a new section of the form factor catalog.

Changes in the GUI mainly address visual issues on high-resolution displays. This may result in some compatibility issues with previous versions.

Much of this release is devoted to internal consolidation and speedup.

  • Standard reflectometry computations become ill conditioned at vanishing transmissions. Previously, we addressed this issue with a bifurcation. We have now implemented a new linear algorithm that is much faster for samples with many layers.
  • The spheroid form factor is now computed without numeric integration. Thanks to Matt Thompson (Australian National University) for the suggestion.
  • Continuous integration tests have been put under control of GitHub Actions, and tentatively been moved to GitHub’s own cloud service. This will reduce waiting times, and thereby make development faster and smoother. Thanks to Andrew Nelson (ANSTO) for insights from the GitHub Actions script he wrote as part of his reflectometry software cross-validation efforts.

We have stopped distributing BornAgain for Python 2.7. We recommend switching to the latest Python, 3.8. The CMake minimum required version has changed to 3.14. The minimum supported MacOS version is now 10.13. For building under Linux, we recommend Ubuntu 20.04 LTS Focal / Debian 11 bullseye.

There are three new examples:

More details are in the CHANGELOG, the issue tracker, and the git history.

As always, we very much welcome your comments and feedback!

June 17, 2020