Expanding the Galactic Haystack: Besançon Model Revisions to SETI Target Volume and an ALMA Millimeter-Wave Survey

To the point

Using the Besançon Galactic Model, Breakthrough Listen with ALMA is shown to have surveyed about 6.1 million stars—roughly 21 times more than previously thought—while four archival calibrator observations found no technosignatures, reframing past null results as a consequence of incomplete star counts and pointing to ALMA’s millimeter-band data as a promising but challenging new SETI window guided by Michael Garrett, Andrew Siemion, and Kelvin Wandia.