A near-infrared SETI experiment: instrument overview

TL;DR

This paper presents the design and development of a near-infrared SETI instrument utilizing advanced avalanche photodiodes for detecting pulsed laser signals, aiming to enhance the search for extraterrestrial communications.

Contribution

It introduces a novel near-infrared pulse search instrument with high sensitivity, low false alarms, and a versatile design based on recent optical SETI experience.

Findings

Instrument design with >1 GHz bandwidth APDs for near-infrared detection

Optimized system for high sensitivity and low false coincidence rates

Initial setup and search strategies for SETI targets described

Abstract

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 builds upon our past optical SETI experiences, and is the first step toward a new, more versatile and sophisticated generation of very fast optical and near-infrared pulse search devices. We present our instrumental design by giving an overview of the opto-mechanical design, detector selection and characterization, signal processing, and integration procedure. This project makes use of near-infrared (950-1650 nm) discrete amplification Avalanche Photodiodes (APD) that have greater than 1 GHz bandwidths with low noise characteristics and moderate gain (~10^4). We have investigated the use of single versus multiple detectors in our instrument (see Maire et al., this conference), and have optimized the system to have both high sensitivity and low false coincidence rates. Our design is optimized for use behind a 1m telescope and includes an optical camera for acquisition and guiding. A goal is to make our instrument relatively economical and easy to duplicate. We describe our observational setup and our initial search strategies for SETI targets, and for potential interesting compact astrophysical objects.