Laser Communication with Proxima and Alpha Centauri using the Solar Gravitational Lens

TL;DR

This study searched for laser signals from Proxima and Alpha Centauri using the Sun's gravitational lensing effect, but found no evidence of laser emissions within the sensitivity limits of 100 Watts over a six-month observation period.

Contribution

It demonstrates the feasibility of using the Solar Gravitational Lens for interstellar laser communication searches and sets upper limits on detectable laser power from these stars.

Findings

No laser signals detected in the observed regions.

The detection threshold was approximately 100 Watts.

The method can detect continuous or pulsed laser emissions.

Abstract

A search was conducted for laser signals, both sub-second pulses and continuous emission, from the regions of the sky opposite Proxima and Alpha Centauri. These regions are located at the foci of the gravitational lensing caused by the Sun, ideal for amplifying transmissions between our Solar System and those two nearest stellar neighbors. During six months in 2020 and 2021, 88000 exposures for Proxima Cen and 47000 exposures for Alpha Cen were obtained. No evidence was detected of light pulses or continuous laser emission in the wavelength range of 380 to 950 nm. We would have detected a laser having a power of just 100 Watts.