The first high frequency technosignature search survey with the Sardinia Radio Telescope
The search for radio signals from technologically advanced extraterrestrial intelligence has traditionally focused around 1.4 GHz. In this paper, we extend the exploration into previously uncharted frequency space, presenting extensive observations at 6 GHz and pioneering the first survey at 18 GHz with the Sardinia Radio Telescope (SRT). Our strategy entailed rigorous observation sessions, totaling 73 h, directed towards the Galactic Center and 72 selected TESS targets—making this the most comprehensive high-frequency technosignature search to date. Our narrowband signal search found no definitive evidence of drifting signals that could suggest an extraterrestrial origin from the surveyed regions. Nevertheless, our efforts have enabled us to set new constraints on the presence of radio emissions from approximately 5 × 1 0 5 stars, establishing an isotropic radiated power limit of 1 . 8 × 1 0 19 W. We also provide a comparative analysis of the ’hits’ recorded across both frequencies to highlight the significance of pursuing technosignature searches at higher frequencies, where the spectral landscape is less congested and more conducive to detection. • First technosignature searches at 6 GHz and 18 GHz with the Sardinia Radio Telescope. • Searches for narrowband drifting signals in the Galactic Center and 72 TESS targets. • Set new constraints on extraterrestrial radio emissions, limiting isotropic power.
Authors
- Lorenzo Manunza
- Alessandro Cabras (ORCID: https://orcid.org/0009-0001-5784-3901)
- Andrew Siemion (ORCID: https://orcid.org/0000-0003-2828-7720)
- Matt Lebofsky (ORCID: https://orcid.org/0000-0002-7042-7566)
- M. Pilia (ORCID: https://orcid.org/0000-0001-7397-8091)
- Tonino Pisanu (ORCID: https://orcid.org/0000-0003-2510-7501)
- Andrea Possenti (ORCID: https://orcid.org/0000-0001-5902-3731)
- Andrea Melis (ORCID: https://orcid.org/0000-0002-4372-0337)
- G. Aresu (ORCID: https://orcid.org/0000-0003-3683-0834)
- Carlo Migoni (ORCID: https://orcid.org/0000-0002-9033-9571)
- Monica Mulas
- A. Corongiu (ORCID: https://orcid.org/0000-0002-5924-3141)
- David H. E. MacMahon (ORCID: https://orcid.org/0000-0001-6950-5072)
- A. Ladu (ORCID: https://orcid.org/0000-0003-1920-9560)
- Giuseppe Carboni (ORCID: https://orcid.org/0000-0002-2056-7501)
- V. Vacca (ORCID: https://orcid.org/0000-0003-1997-0771)
- E. Molinari (ORCID: https://orcid.org/0000-0002-1742-7735)
- F. Loi (ORCID: https://orcid.org/0000-0002-8627-6627)
- Silvia Casu (ORCID: https://orcid.org/0000-0002-0154-3571)
- Antonio Poddighe (ORCID: https://orcid.org/0000-0002-1177-4998)
- M. Burgay (ORCID: https://orcid.org/0000-0002-8265-4344)
- S. Croft (ORCID: https://orcid.org/0000-0003-4823-129X)
- A. Pellizzoni (ORCID: https://orcid.org/0000-0002-4590-0040)
- Karen I. Perez (ORCID: https://orcid.org/0000-0002-6341-4548)
- M. Trudu (ORCID: https://orcid.org/0000-0002-1530-0474)
- E. Egron (ORCID: https://orcid.org/0000-0002-1532-4142)
- M. Murgia (ORCID: https://orcid.org/0000-0002-4800-0806)
- D. Perrodin (ORCID: https://orcid.org/0000-0002-1806-2483)
- Erika Rea
- Vishal Gajjar (ORCID: https://orcid.org/0000-0002-8604-106X)
- Tiziana Coiana
- O. Johnson (ORCID: https://orcid.org/0000-0002-5927-0481)
- Alice Vendrame
- Luca Pizzuto (ORCID: https://orcid.org/0000-0002-9176-3673)
- Paolo Soletta (ORCID: https://orcid.org/0000-0003-0824-0562)
Institutions
- University of Cagliari (IT)
- Trinity College Dublin (IE)
- University of Oxford (GB)
- Istituto Nazionale di Fisica Nucleare, Sezione di Cagliari (IT)
- Osservatorio Astronomico di Cagliari (IT)
- Columbia University (US)
- Search for Extraterrestrial Intelligence (US)
- University of Bologna (IT)
- University of California, Berkeley (US)
Publication Details
- Journal
- Acta Astronautica
- Published
- 2025-04-12
- DOI
- https://doi.org/10.1016/j.actaastro.2025.04.007
- Citations
- 4
- Primary Topic
- Space Science and Extraterrestrial Life
- Type
- article
- Field-Weighted Citation Impact
- 4.62