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Rotational modulation in IUE spectra of cool dwarf chromospheres. I - Data analysis and period search techniquesTime-sequenced IUE spectra of a number of a bright F-K dwarfs have been used to investigate rotational modulation in several important chromospheric and transition emission lines. Stellingwerf's phase dispersion minimization (PDM) technique forms the basis of this time-series analysis of these sparsely sampled, irregularly spaced observational sequences, which consist of no more than 13 spectra in any one season. In such highly sample-limited time series, the resultant PDM spectrum is greatly complicated by overlapping alias orders which invariably produce strong interference effects, but the deliberately irregular sampling has proven of value in the development of techniques to identify the intrinsic stellar flux modulation period. Two stars are selected to illustrate these new techniques in detail.
Document ID
19910050425
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Hallam, K. L.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Altner, B.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Endal, A. S.
(Applied Research Corp. Landover, MD, United States)
Date Acquired
August 15, 2013
Publication Date
May 10, 1991
Publication Information
Publication: Astrophysical Journal, Part 1
Volume: 372
ISSN: 0004-637X
Subject Category
Astrophysics
Accession Number
91A35048
Distribution Limits
Public
Copyright
Other

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