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Initial results from Harvard all-sky optical SETI

Howard, Andrew and Horowitz, Paul and Mead, Curtis and Sreetharan, Pratheev and Gallicchio, Jason and Howard, Steve and Coldwell, Charles and Zajac, Joe and Sliski, Alan (2007) Initial results from Harvard all-sky optical SETI. Acta Astronautica, 61 (1-6). pp. 78-87. ISSN 0094-5765.

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We report initial results from the Harvard/Planetary Society all-sky search for pulsed optical signals from other civilizations, which saw “first light” on 11 April 2006 after 6 years of planning and construction. To survey the northern sky (-20∘<δ<+70∘), our 1.8-m spherical f/2.5 optical telescope images a 1.6∘×0.2∘ patch of sky on two matched focal planes with a total of 1024 photomultiplier tube pixels. Each pair of pixels images the same 2.3 square arcminute patch of sky, and fast electronics filters the incoming visual band light for nanosecond pulses. Coincident optical flashes in a pair of pixels triggers one of 32 PulseNet full-custom chips to record the pulse profiles at nanosecond resolution. This experiment is an all-sky, kilopixel evolution of our targeted search. Its meridian transit survey mode requires ∼150 clear nights to cover the northern sky with 1-min dwell time per source point. Focus in this talk will be given to describing the capabilities of the all-sky search instrument, the first few months observations, and constraints that these observations place on the density of pulsed optical signals in the galaxy.

Item Type:Article
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Howard, Andrew0000-0001-8638-0320
Additional Information:© 2007 Elsevier Ltd. Available online 16 April 2007.
Subject Keywords:Extraterrestrial intelligence; Astrobiology; Instrumentation; Detectors
Issue or Number:1-6
Record Number:CaltechAUTHORS:20170705-152326981
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Official Citation:Andrew Howard, Paul Horowitz, Curtis Mead, Pratheev Sreetharan, Jason Gallicchio, Steve Howard, Charles Coldwell, Joe Zajac, Alan Sliski, Initial results from Harvard all-sky optical SETI, Acta Astronautica, Volume 61, Issue 1, 2007, Pages 78-87, ISSN 0094-5765, (
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:78776
Deposited By: Tony Diaz
Deposited On:06 Jul 2017 22:55
Last Modified:03 Oct 2019 18:12

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