HamSCI Ray Tracing is a working group within HamSCI for amateur radio operators, citizen scientists, software developers, and professional researchers interested in HF propagation and ionospheric science. The group promotes the development and use of open-source HF ray-tracing tools, the validation of ionospheric models using HamSCI observations, and collaborative studies of space weather and unusual HF propagation. It also provides a forum for tutorials, technical discussions, software feedback, and community research projects.

The group’s flagship effort is a fully open-source 3D HF ray-tracing toolkit, implemented natively in Python from the Jones & Stephenson (1975) ray-tracing formulation. This toolkit is independent of the team’s earlier PyLap toolkit — an open-source Python wrapper for the proprietary PHaRLAP ray-tracing engine — which remains available as prior, related work. The new toolkit integrates ionospheric model output (e.g., IRI, SAMI3, and coupled SAMI3/WACCM-X) and HamSCI observational data (RBN, PSKReporter, WSPRNet, and PSWS/GRAPE Doppler receivers) to validate ionospheric models and to study anomalous HF propagation, including Equatorial Plasma Bubbles (EPBs) and understudied off-great-circle (side-scatter) paths.

This work is supported by NASA ROSES 2024 B.21 Heliophysics Citizen Science Investigations (H-CSI), award 80NSSC26K0051, “Ionospheric Model Validation and Development of an Open-Source HF Ray-Tracing Toolkit Leveraging HamSCI Citizen Science Data” (PI: Kornyanat Hozumi, University of Scranton).

Part of this work is also supported by the Office of Naval Research (ONR), award N000142612000, “Crowdsourced Observations for Ionospheric Model Validation and a Diagnostic Approach for Forecasting Equatorial Spread F” (PI: Kornyanat Hozumi, University of Scranton). Only the ray-tracing-related portion of that broader project is part of this working group; see Goals for the specific objectives it supports.

For updates and to join bi-weekly meetings, join the Google Group here. Meeting announcements are sent out on the mailing list.