Related papers: A Proposed Method for a Photon-Counting Laser Cohe…
Natural laser emission may be produced whenever suitable atomic energy levels become overpopulated. Strong evidence for laser emission exists in astronomical sources such as Eta Carinae, and other luminous stars. However, the evidence is…
We have searched for nonastrophysical emission lines in the optical spectra of 577 nearby F, G, K, and M main-sequence stars. Emission lines of astrophysical origin would also have been detected, such as from a time--variable chromosphere…
The idea of searching for optical signals from extraterrestrial civilizations has become increasingly popular over the last five years, with dedicated projects at a number of observatories. The method relies on the detection of a brief (few…
The Panoramic SETI (Search for Extraterrestrial Intelligence) experiment (PANOSETI) aims to detect and quantify optical transients from nanosecond to second precision over a large field-of-view ($\sim$4,450 square-degrees). To meet these…
The Search for Extra-terrestrial Intelligence (SETI) aims to find technological signals of extra-solar origin. Radio frequency SETI is characterized by large unlabeled datasets and complex interference environment. The infinite…
We present a simple and flexible technique for identifying the onset of coherent emission in lasers, from the mesoscale to the nanoscale, which makes use of photon counting and a small amplitude modulation added to the pump. The optimal…
We examined archived observations of 2,821 stars taken by the high-resolution ESO HARPS spectrograph to search for potential narrow-band laser emissions from extraterrestrial sources. From one observation of each star, our search algorithm…
Previous and ongoing searches for extraterrestrial optical and infrared nanosecond laser pulses and narrow line-width continuous emissions have so far returned null results. At the commonly used observation cadence of $\sim 10^{-9}\,$s,…
The modern search for extraterrestrial intelligence (SETI) began with the seminal publications of Cocconi & Morrison (1959) and Schwartz & Townes (1961), who proposed to search for narrow-band signals in the radio spectrum, and for optical…
The searches for other life and for intelligence are fundamental problems that science faces today. Most searches so far have been focused on radio, but optical laser communication is an alternative, well suited for a ground-based…
In the cm-wavelength range, an extraterrestrial electromagnetic narrow band (sine wave) beacon is an excellent choice to get alien attention across interstellar distances because 1) it is not strongly affected by interstellar /…
The invention of the laser immediately enabled the detection of nonlinear photon-matter interactions, as manifested for example by Franken et al.'s detection of second-harmonic generation. With the recent advancement in high-power,…
A region 140 square degrees toward the Galactic Centre was searched for monochromatic optical light, both pulses shorter than 1 sec and continuous emission. A novel instrument was constructed that acquires optical spectra of every point…
Optical SETI (Search for Extraterrestrial Intelligence) instruments that can explore the very fast time domain, especially with large sky coverage, offer an opportunity for new discoveries that can complement multimessenger and time domain…
We are designing and constructing a new SETI (Search for Extraterrestrial Intelligence) instrument to search for direct evidence of interstellar communications via pulsed laser signals at near-infrared wavelengths. The new instrument design…
We report a proof-of-concept demonstration of a tunable infrared (IR) optical coherence tomography (OCT) technique with detection of only visible range photons. Our method is based on the nonclassical interference of frequency correlated…
A technique complementary to those for spectral lines is proposed for the observation of continuum radiation. As, quantum mechanically, the radiation is a mixture of pure states, it should be possible to measure the temporal coherence of…
The transmission rate of communication between radio telescopes on Earth and extraterrestrial intelligence (ETI) is here calculated up to distances of 1000 light years. Both phase-shift-keying (PSK) and frequency-shift keying (FSK)…
The main purpose of this article is to make Astronomers aware that Searches for Extraterrestrial Intelligence can be carried out by analyzing standard astronomical spectra, including those they already have taken. Simplicity is the…
We present a search for laser emission coming from point sources in the vicinity of 2796 stars, including 1368 Kepler Objects of Interest (KOIs) that host one or more exoplanets. We search for extremely narrow emission lines in the…