Multibeam SETI Observations toward Nearby M dwarfs with FAST

TL;DR

This study used FAST to conduct targeted SETI observations of three nearby M dwarfs with exoplanets, searching for technosignatures in the 1.05-1.45 GHz range, but found no confirmed extraterrestrial signals.

Contribution

First application of FAST for targeted SETI on M dwarfs with exoplanets using multibeam coincidence matching in the 1.05-1.45 GHz band.

Findings

No confirmed extraterrestrial signals detected.

An initial unusual signal was ultimately identified as non-ET origin.

Demonstrated FAST's capability for sensitive SETI observations.

Abstract

The search for extraterrestrial intelligence (SETI) targeted searches aim to observe specific areas and objects to find possible technosignatures. Many SETI researches have focused on nearby stars and their planets in recent years. In this paper, we report a targeted SETI observations using the most sensitive L-band Five-hundred-meter Aperture Spherical radio Telescope (FAST) toward three nearby M dwarfs, all of which have been discovered exoplanet candidates. The minimum equivalent isotropic radiant power of the lower limit from the three sources we can detect is $6.19 \times 10^{8}$ W, which is well within the reach of current human technology. Applying the multibeam coincidence matching (MBCM) blind search mode, we search for narrowband drifting signals across 1.05-1.45 GHz in each of the two orthogonal linear polarization directions. An unusual signal at 1312.50 MHz detected from the observation toward AD Leo originally piqued our interest. However, we finally eliminate the possibility of an extraterrestrial origin based on much evidence, such as the polarization, frequency, and beam coverage characteristics.