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Title: Searching for Broadband Pulsed Beacons from 1883 Stars Using Neural Networks
The search for extraterrestrial intelligence at radio frequencies has largely been focused on continuous-wave narrowband signals. We demonstrate that broadband pulsed beacons are energetically efficient compared to narrowband beacons over longer operational timescales. Here, we report the first extensive survey searching for such broadband pulsed beacons toward 1883 stars as a part of the Breakthrough Listen’s search for advanced intelligent life. We conducted 233 hr of deep observations across 4–8 GHz using the Robert C. Byrd Green Bank Telescope and searched for three different classes of signals with artificial (or negative) dispersion. We report a detailed search—leveraging a convolutional neural network classifier on high-performance GPUs—deployed for the very first time in a large-scale search for signals from extraterrestrial intelligence. Due to the absence of any signal-of-interest from our survey, we place a constraint on the existence of broadband pulsed beacons in our solar neighborhood: ≲1 in 1000 stars have transmitter power densities ≳10^5 W Hz^−1 repeating ≤500 s at these frequencies.  more » « less
Award ID(s):
2138147
PAR ID:
10585699
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more » ; ; « less
Publisher / Repository:
The American Astronomical Society
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
932
Issue:
2
ISSN:
0004-637X
Page Range / eLocation ID:
81
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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