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Title: Hycean Exoplanets as Targets for Technosignature Detection: A Case Study of K2-18 b in the 3–10 GHz Band
Abstract Recently the James Webb Space Telescope performed near-infrared spectroscopic observations of the atmosphere of a potential Hycean exoplanet, K2-18 b. These spectra provided evidence of methane and carbon dioxide in its atmosphere, along with a possible line attributed to biomarker dimethyl sulfide. In this work, we present triggered narrow-band radio observations of K2-18 b conducted using the Allen Telescope Array over 3–10 GHz, in search of signs of artificially produced radio emissions (technosignatures). We do not find any spatially isolated signals in the direction of K2-18 b, establishing lower and upper limits on the equivalent isotropic radiated power (∼1013–1016 W) of potential extraterrestrial transmitters between 3 and 10 GHz. This study emphasizes the importance of ongoing observations to further explore K2-18 b’s potential as a candidate for the detection of technosignatures.  more » « less
Award ID(s):
2138147
PAR ID:
10480914
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
American Astronomical Society
Date Published:
Journal Name:
Research Notes of the AAS
Volume:
7
Issue:
11
ISSN:
2515-5172
Page Range / eLocation ID:
233
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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