From: Amara Graps (Amara.Graps@mpi-hd.mpg.de)
Date: Tue Feb 12 2002 - 08:15:42 MST
Results from a search for some 'unnatural' emission from nearby stars.
Amara
http://xxx.lanl.gov/abs/astro-ph/0112479
Astrophysics, abstract
astro-ph/0112479
From: Geoffrey W. Marcy <gmarcy@etoile.berkeley.edu>
Date (v1): Thu, 20 Dec 2001 13:32:07 GMT (41kb)
Date (revised v2): Mon, 11 Feb 2002 09:35:16 GMT (41kb)
Optical SETI: A Spectroscopic Search for Laser Emission from Nearby Stars
Authors: Amy E. Reines (1), Geoffrey W. Marcy (1,2) ((1) San Francisco State
University Department of Physics and Astronomy, (2) University of California
Berkeley Department of Astronomy)
Comments: 27 pages, 11 figures, uses aastex.sty
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 or infalling
comets. We examined ~20 spectra per star obtained during four
years with the Keck/HIRES spectrometer at a resolution of 5 km/s,
with a detection threshold 3% of the continuum flux level. We
searched each spectrum from 4000-5000 angstroms for emission lines
having widths too narrow to be natural from the host star, as well
as for lines broadened by astrophysical mechanisms. We would have
detected lasers that emit a power, P>60 kW, for a typical beam
width of ~0.01 arcsec (diffraction-limit from a 10-m aperture) if
directed toward Earth from the star. No lines consisstent with
laser emission were found.
Paper: PostScript, PDF, or Other formats
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Amara Graps, PhD | Max-Planck-Institut fuer Kernphysik
Heidelberg Cosmic Dust Group | Saupfercheckweg 1
+49-6221-516-543 | 69117 Heidelberg, GERMANY
Amara.Graps@mpi-hd.mpg.de * http://www.mpi-hd.mpg.de/dustgroup/~graps
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