Carmen Choza - SETI Institute

Abstract: Radio narrowband technosignatures have been a cornerstone of SETI efforts since the field's inception, dating back to Project Ozma in 1960. These signals remain a prime target due to their distinctiveness from natural astrophysical phenomena and their potential for efficient interstellar communication. Despite the emergence of new search modalities, narrowband radio SETI maintains its relevance due to the minimal assumptions required about alien technology and the vast, as-yet unexplored parameter space. The GBT's ability to detect extremely faint signals across a wide range of frequencies makes it an invaluable asset in probing deeper into the cosmos for signs of technological intelligence.
The search for extraterrestrial intelligence (SETI) continues to evolve, with Breakthrough Listen's efforts using the Green Bank Telescope (GBT) playing a key role in those advancements. This presentation provides a recent overview of how the single-dish SETI program is expanding our cosmic reach through three key areas: high-impact follow-up, maximizing the field of view, and enhancing search techniques. Recent novel searches of nearby galaxies and follow-up of promising technosignature host candidates have allowed more efficient allocation of observational resources, maximizing the potential for significant discoveries while expanding search parameters beyond traditional bounds and allowing us to place stringent limits on the probability of technosignature presence outside our solar system. Critical improvements to the search pipeline include advanced filtering mechanisms, refined logic, and increased sensitivity, enabling more effective detection and characterization of potential technosignatures. By leveraging the unique capabilities of the GBT and implementing these improved methodologies, Breakthrough Listen is significantly expanding the scope and depth of the search for extraterrestrial intelligence.