The Breakthrough Listen Search for Intelligent Life: Technosignature Search of Transiting TESS Targets of Interest

TL;DR

This study conducted a comprehensive radio search for technosignatures in 61 TESS exoplanet candidate targets during their transit, finding no signals and setting upper limits on potential extraterrestrial transmitters' power.

Contribution

It presents the first targeted radio technosignature search of TESS Targets of Interest during transits, expanding the scope of SETI efforts with new observational constraints.

Findings

No technosignature signals detected in the survey.

Fewer than 52%, 20%, 16%, and 15% of TESS TOIs have transmitters above certain power thresholds.

Established upper limits on transmitter power for TESS exoplanet candidates.

Abstract

The Breakthrough Listen Initiative, as part of its larger mission, is performing the most thorough technosignature search of nearby stars. Additionally, Breakthrough Listen is collaborating with scientists working on NASAs Transiting Exoplanet Survey Satellite (TESS), to examine TESS Targets of Interest (TOIs) for technosignatures. Here, we present a $1-11$ $\textrm{GHz}$ radio technosignature search of $61$ TESS TOIs that were in transit during their Breakthrough Listen observation at the Robert C. Byrd Green Bank Telescope. We performed a narrowband Doppler drift search with a minimum S/N threshold of $10$, across a drift rate range of $\pm 4$ $\textrm{Hz}$ $\textrm{s}$ $^{-1}$, with a resolution of $3$ $\textrm{Hz}$. We removed radio frequency interference by comparing signals across cadences of target sources. After interference removal, there are no remaining events in our survey, and therefore no technosignature signals-of-interest detected in this work. This null result implies that at L, S, C, and X bands, fewer than $52\textrm{%}$, $20\textrm{%}$, $16\textrm{%}$, and $15\textrm{%}$, respectively, of TESS TOIs possess a transmitter with an equivalent isotropic radiated power greater than a few times $10^{14}$ $\textrm{W}$.