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The interstellar D1 line at high resolutionObservations at a resolving power or a velocity resolution are reported of the interstellar D(sub 1) line of Na I in the spectra of gamma Cas, delta Ori, epsilon Ori, pi Sco, delta Cyg, and alpha Cyg. An echelle grating was used in a double-pass configuration with a CCD detector in the coude spectrograph of the 2.7 m reflector at McDonald Observatory. At least 42 kinematically distinct clouds are detected along the light paths to the five more distant stars, in addition to a single cloud seen toward delta Cyg. The absorption lines arising in 13 of the clouds are sufficiently narrow and unblended to reveal clearly resolved hyperfine structure components split by 1.05 km/s. An additional 13 clouds apparently show comparably narrow, but more strongly blended, lines. For each individual cloud, upper limits T(sub max) and (v sub t)(sub max) on the temperature and the turbulent velocity, respectively, are derived by fitting the observed lines with theoretical absorption profiles.
Document ID
Document Type
Preprint (Draft being sent to journal)
Hobbs, L. M.
(Yerkes Observatory Williams Bay, WI, United States)
Welty, D. E.
(Yerkes Observatory Williams Bay, WI, United States)
Date Acquired
September 6, 2013
Publication Date
January 1, 1990
Subject Category
Report/Patent Number
NAS 1.26:184915
Accession Number
Funding Number(s)
Distribution Limits
Work of the US Gov. Public Use Permitted.
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