Ca II H and K measurements made at Mount Wilson Observatory, 1966-1983

Journal Article · Wed May 01 04:00:00 EDT 1991 · Astrophysical Journal, Supplement Series; (United States)

DOI:https://doi.org/10.1086/191572· OSTI ID:5541075

Duncan, D K; Wilson, O C; Preston, G W; Frazer, J; Vaughan, A H ^[1]

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1. Observatories of the Carnegie Institution of Washington, Pasadena, CA (USA)

Summaries are presented of the photoelectric measurements of stellar Ca II H and K line intensity made at Mount Wilson Observatory during the years 1966-1983. These results are derived from 65,263 individual observations of 1296 stars. For each star, for each observing season, the maximum, minimum, mean, and variation of the instrumental H and K index 'S' are given, as well as a measurement of the accuracy of observation. A total of 3110 seasonal summaries are reported. Factors which affect the ability to detect stellar activity variations and accurately measure their amplitudes, such as the accuracy of the H and K measurements and scattered light contamination, are discussed. Relations are given which facilitate intercomparison of 'S' values with residual intensities derived from ordinary spectrophotometry, and for converting measurements to absolute fluxes. 28 refs.

• OSTI ID: 5541075
• Journal Information: Astrophysical Journal, Supplement Series; (United States), Journal Name: Astrophysical Journal, Supplement Series; (United States) Vol. 76; ISSN APJSA; ISSN 0067-0049
• Country of Publication: United States
• Language: English

Related Subjects

640102* -- Astrophysics & Cosmology-- Stars & Quasi-Stellar
Radio & X-Ray Sources
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ALKALI METALS
ALKALINE EARTH METALS
CALCIUM
CHEMICAL COMPOSITION
DATA ANALYSIS
DETECTION
ELEMENTS
HYDROGEN
METALS
NONMETALS
POTASSIUM
SPECTROPHOTOMETRY
STELLAR ACTIVITY
VARIATIONS