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arXiv · 2608.18275

The VLA and High-Frequency SETI: Expanding the Search for Life

Talon Myburgh·Noah Stiegler·Chenoa D. Tremblay·Joe S. Bright·Ross A. Donnachie
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Abstract

The Commensal Open-Source Multimode Interferometer Cluster (COSMIC) runs software that searches for technologies elsewhere in the Universe ("technosignatures") using the Karl G. Jansky Very Large Array (VLA). Specifically, it searches for narrowband signals that drift in frequency over time as a result of Doppler motions. Although this is the first study of high-frequency technosignatures that has been published from the COSMIC system on the VLA, it follows closely on previous work completed by an undergraduate research intern. Within the field of view of the VLA, the software on COSMIC creates coherent beams directed toward stars that may contain exoplanets from the Gaia catalogue. The recorded results follow a real-time software pipeline and are examined for technosignatures. Using a Taylor-Tree De-Dispersion algorithm to find narrow-band drifting signals, each recorded beam (coherent and incoherent) is searched for signals with a drift-rate with magnitudes up to $\pm$50Hz/s. All detections are stored as "hits" with the relevant snippet of data stored for posterity. The purpose of this work is to extend the high-frequency search by reviewing data from February 2024 to the present. Our study examines the impact of previously implemented and novel filters to find a selection of candidate signals. At the final stage of the pipeline, our objective is to study these resultant candidate signals spatially through imaging. The observations therefore probe regions of frequency and signal parameter space that have received comparatively limited coverage in previous SETI surveys.

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Talon Myburgh, Noah Stiegler, Chenoa D. Tremblay, Joe S. Bright, Ross A. Donnachie. 2026-08-18. The VLA and High-Frequency SETI: Expanding the Search for Life. https://doi.org/10.1016/j.actaastro.2026.08.032

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