A Proposed Method for a Photon-counting Laser Coherence Detection System to Complement Optical SETI. (22nd May 2019)

• Record Type: Journal Article
• Authors: Benton, David M.
• Is Part Of: Publications of the Astronomical Society of the Pacific. Volume 131:Number 1001(2019)
• Publication Date: 2019-05-22
• Subjects: photon counting -- coherence -- seti; Astronomy -- Periodicals; Astronomy; Periodicals; Periodicals; 520.5
• DOI: 10.1088/1538-3873/ab1a46
• Languages: English
• ISSNs: 0004-6280

Abstract

Abstract: The detection of laser radiation originating from space is a positive indicator of Extra Terrestrial Intelligence (ETI). Thus far, the optical search for ETI (OSETI) has looked for enhanced brightness in the form of either narrow-band spectral emission or time correlated photons from laser pulses. In this paper, it is proposed to look for coherence properties of incoming light in a manner that can distinguish against atomic emission lines. The use of photon-sensitive detectors and a modulating asymmetric interferometer has been modeled. The results suggest that the sensitivity of detection for continuous laser sources would be better than current spectroscopic approaches, with detection thresholds of <1 photon s −1 m −2 against a background with a spectral bandwidth of 0.1 nm over an observation time of 750 s.