SynIM

Synthetic Interaction Matrix generator for Adaptive Optics systems

Overview

SynIM is a Python package for computing synthetic interaction matrices, projection matrices, and covariance matrices for adaptive optics (AO) systems. It supports both Single Conjugate AO (SCAO), Laser Tomography AO (LTAO), Ground Layer AO (GLAO) and Multi-Conjugate AO (MCAO) configurations with Shack-Hartmann sensors. It also supports GPU acceleration. Some of its functionalities are provided by SPECULA.

Key Features

• 🔧 Interaction matrices for DM-WFS combinations (SCAO/MCAO)
• 📊 Projection matrices for DM-Layer tomography (MCAO/LTAO)
• 📈 Covariance matrices for MMSE reconstructor optimization
• ⚙️ YAML/PRO configuration with automatic parameter parsing
• 💾 SPECULA-compatible FITS format for data exchange
• 🎯 Smart caching to minimize redundant computations
• 🚀 GPU acceleration via CuPy for high-performance computation
• 🧭 Mis-registration geometry (synim.registration): a geometric (not pixel-based) model of the relation between global (WFS/DM/guide-star) and local (per-pair) mis-registration in MCAO/GLAO systems, its inversion, and sensitivity/noise analysis - see the documentation

Documentation

Full documentation available at: synim.readthedocs.io

Slope Computation Methods

SynIM supports two slope computation methods for interaction matrices:

• derivatives (default): compute numerical derivatives on the transformed phase
• telsum (optional): compute telescoping sum from phase differences in each subaperture

The default behavior is derivatives. To enable telescoping sum, pass slope_method='telsum' when calling the low-level interaction-matrix APIs.

Requirements

• Python ≥ 3.8
• numpy, scipy, matplotlib
• specula - AO simulation framework
• cupy - GPU acceleration (optional, requires CUDA)

Contributing to SynIM

To contribute to SynIM, follow these steps:

1. Fork this repository.
2. Create a branch: git checkout -b <branch_name>
3. Make your changes and add tests for the new functionality.
4. Commit your changes: git commit -m '<commit_message>'
5. Push to the branch: git push
6. Create the pull request.

We require tests for all new features to ensure the stability of the project.

Citation

If you use SynIM in your research, please cite:

@misc{agapito2026synim,
  title         = {SynIM: a high-performance GPU-accelerated Python library for
                   synthetic interaction and tomographic reconstruction matrices
                   in next-generation adaptive optics},
  author        = {Agapito, Guido and Rossi, Fabio and Puglisi, Alfio},
  year          = {2026},
  eprint        = {2606.07759},
  archivePrefix = {arXiv},
  primaryClass  = {astro-ph.IM},
  url           = {https://arxiv.org/abs/2606.07759}
}

License

MIT License - see LICENSE file for details.

Authors

• Guido Agapito - INAF - Osservatorio Astrofisico di Arcetri

Acknowledgments

It was built as part of the MORFEO project.