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Diode laser heterodyne observations of silicon monoxide in sunspots - A test of three sunspot modelsAbsorption features from the 8 micron SiO fundamental (upsilon = 1-0) and hot bands (upsilon = 2-1) have been observed in sunspots at sub-Doppler resolution using a ground-based tunable diode laser heterodyne spectrometer. The observed line widths suggest an upper limit of 0.5 km/s for the microturbulent velocity in sunspot umbrae. Since the silicon monoxide abundance is very sensitive to sunspot temperature, the measured equivalent widths permit an unambiguous determination of the temperature-pressure relation in the upper layers of the umbral atmosphere. In the region of SiO line formation (log P sub g = 3.0-4.5), the results support the sunspot model suggested by Stellmacher and Wiehr (1970).
Document ID
19830053425
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Glenar, D. A. (Pennsylvania State University University Park, PA, United States)
Deming, D. (Pennsylvania State Univ. University Park, PA, United States)
Jennings, D. E. (Pennsylvania State Univ. University Park, PA, United States)
Kostiuk, T. (Pennsylvania State Univ. University Park, PA, United States)
Mumma, M. J. (NASA Goddard Space Flight Center Infrared and Radio Astronomy Branch, Greenbelt, MD, United States)
Date Acquired
August 11, 2013
Publication Date
June 1, 1983
Publication Information
Publication: Astrophysical Journal, Part 1
Volume: 269
ISSN: 0004-637X
Subject Category
SOLAR PHYSICS
Funding Number(s)
CONTRACT_GRANT: NGT-39-009-800
CONTRACT_GRANT: NGL-39-009-003
Distribution Limits
Public
Copyright
Other