Paper
3 August 2001 Targeted and all-sky search for nanosecond optical pulses at Harvard-Smithsonian
Paul Horowitz, Charles M. Coldwell, Andrew B. Howard, David W. Latham, Robert Stefanik, Jonathan Wolff, Joe M. Zajac
Author Affiliations +
Abstract
We have built a system to detect nanosecond pulsed optical signals from a target list of some 10,000 sun-like stars, and have made some 20,000 observations during its two years of operation. A beamsplitter feeds a pair of hybrid avalanche photodetectors at the focal plane of the 1.5m Cassegrain at the Harvard/Smithsonian Oak Ridge Observatory (Agassiz Station), with a coincidence triggering measurement of pulse width and intensity at sub-nanosecond resolution. A flexible web-enabled database, combined with mercifully low background coincidence rates (approximately 1 event per night), makes it easy to sort through far-flung data in search of repeated events from any candidate star. An identical system will soon begin observations, synchronized with ours, at the 0.9m Cassegrain at Princeton University. These will permit unambiguous identification of even a solitary pulse. We are planning an all-sky search for optical pulses, using a dedicated 1.8m f/2.4 spherical glass light bucket and an array of pixelated photomultipliers deployed in a pair of matched focal planes. The sky pixels, 1.5 arcmin square, tessellate a 1.6 by 0.2 degree patch of sky in transit mode, covering the Northern sky in approximately 150 clear nights. Fast custom IC electronics will monitor corresponding pixels for coincident optical pulses of nanosecond timescale, triggering storage of a digitized waveform of the light flash.
© (2001) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Paul Horowitz, Charles M. Coldwell, Andrew B. Howard, David W. Latham, Robert Stefanik, Jonathan Wolff, and Joe M. Zajac "Targeted and all-sky search for nanosecond optical pulses at Harvard-Smithsonian", Proc. SPIE 4273, The Search for Extraterrestrial Intelligence (SETI) in the Optical Spectrum III, (3 August 2001); https://doi.org/10.1117/12.435364
Lens.org Logo
CITATIONS
Cited by 23 scholarly publications.
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Stars

Telescopes

Signal processing

Sensors

Observatories

Electronics

Beam splitters

Back to Top