H and K Emission in Late-Type Stars: Dependence of Line Width on Luminosity and Related Topics.

Wilson, O. C.; Bappu, M. K. V.

doi:10.1086/146339

Cited by 241 publications

(131 citation statements)

References 1 publication

Supporting

Mentioning

120

Contrasting

Unclassified

Order By: Relevance

“…As already stated, their work is based on the width measurements available in the literature, mostly from Wilson (1967Wilson ( , 1976, wich suffer from low spectral accuracy. We note here that such measurements are based on the definition of W given in Wilson & Bappu (1957), corrected for instrumental broadening as in Wilson (1959) (see Sect. 3).…”

Section: Comparison With Other Resultsmentioning

confidence: 99%

See 1 more Smart Citation

The Wilson–Bappu effect: A tool to determine stellar distances

Pace

Pasquini

Ortolani

2003

A&A

View full text Add to dashboard Cite

Abstract. Wilson & Bappu (1957) have shown the existence of a remarkable correlation between the width of the emission in the core of the K line of CaII and the absolute visual magnitude of late-type stars. Here we present a new calibration of the Wilson-Bappu effect based on a sample of 119 nearby stars. We use, for the first time, width measurements based on high resolution and high signal to noise ratio CCD spectra and absolute visual magnitudes from the Hipparcos database. Our primary goal is to investigate the possibility of using the Wilson-Bappu effect to determine accurate distances to single stars and groups. The result of our calibration fitting of the Wilson-Bappu relationship is M V = 33.2−18.0 log W 0 , and the determination seems free of systematic effects. The root mean square error of the fitting is 0.6 mag. This error is mostly accounted for by measurement errors and intrinsic variability of W 0 , but in addition a possible dependence on the metallicity is found, which becomes clearly noticeable for metallicities below [Fe/H] ∼ −0.4. This detection is possible because in our sample [Fe/H] ranges from −1.5 to 0.4. The Wilson-Bappu effect can be used confidently for all metallicities not lower than ∼−0.4, including the LMC. While it does not provide accurate distances to single stars, it is a useful tool to determine accurate distances to clusters and aggregates, where a sufficient number of stars can be observed. We apply the Wilson-Bappu effect to published data of the open cluster M 67; the retrieved distance modulus is of 9.65 mag, in very good agreement with the best distance estimations for this cluster, based on main sequence fitting.

show abstract

Section: Comparison With Other Resultsmentioning

confidence: 99%

“…Wilson & Bappu (1957) have shown the existence of a remarkable correlation between the width of the emission in the core of the K line of CaII and the absolute visual magnitude of late-type stars. Here we present a new calibration of the Wilson-Bappu effect based on a sample of 119 nearby stars.…”

mentioning

confidence: 99%

The Wilson–Bappu effect: A tool to determine stellar distances

Pace

Pasquini

Ortolani

2003

A&A

View full text Add to dashboard Cite

show abstract

“…The mass function is very small, 0.0006 90î o > and it is probably seen at a small angle of inclination. The Can emission is exceptionally strong (Wilson and Bappu 1957). The spectral type, G8 III-IV and intrinsic variability (Archer 1960) indicates that it may be similar to the RS Canum Venaticorum type binaries but viewed approximately pole-on (Hall 1976).…”

Section: Resultsmentioning

confidence: 94%

Evidence for radio emission from the giant binary lam and and a search for emission from other stars.

Bath¹,

Wallerstein²

1976

PASP

View full text Add to dashboard Cite

We have conducted a survey of 135 peculiar and variable stars in a search for continuum radio emission at 6 cm using the 140-foot and 300-foot telescopes at Green Bank. One positive new detection is reported and flux densities for Algol during the period 7-10 March are given. Two further sources near the blue variable V426 Oph and the symbiotic carbon star UV Aur are discussed.The new source, A And, is a giant binary related to the RS CVn binaries. It provides additional support for the identification of this class of binaries as being strongly prone to radio emission.

show abstract

“…The empirical relationship between the absolute visual magnitude of a star and the full widths at half maximum (FWHM} of the .emission cores in the Ca II H and K lines (Wilson and Bappu, 1957) may be expressed in terms of the more fundamental atmospheric parameters gravity, g, and effective temperature, Te (Reimers, 1973;Neckel, 1974).…”

Section: Surface Gravities Using the Wilson-bappu Effectmentioning

confidence: 99%

Late-Type Ca II Emission-Line Stars in the Southern Hemisphere

Collier

1983

Astrophysics and Space Science Library

View full text Add to dashboard Cite

The results of a photometric and spectroscopic study of twenty-three late-type southern stars with strong Ca II H and K emission are presented.The presence of photometric variability, with similar properties to the photometric wave phenomenon seen in the RS Canum Venaticorum binaries, is noted in thirteen of the fifteen stars for which extensive photometry was obtained.Of twenty stars for which high-resolution radial velocity measurements were obtained, ten are found to be single-lined and seven are found to be double-lined spectroscopic binaries.Orbital periods are determined for eight previously-unknown binaries.The periods range from 0.66 up to 53.9 days. ca II H and K spectra of ten of the program stars yield line surface fluxes in the range in the H and·K emission cores. The high proportion of single-lined RS CVn binaries in the sample is discussed in terms of selection effects.The space density of RS CVn systems with mass ratios less than q ~ 0.8 is found to be at least equal to that of the q ~ 0.8 systems. This implies a total space density of at systems in the Galactic plane is found to be 1.9 x 10 pc by this method, in reasonable agreement with the observed .value.ii CONTENTS

show abstract

H and K Emission in Late-Type Stars: Dependence of Line Width on Luminosity and Related Topics.

Cited by 241 publications

References 1 publication

The Wilson–Bappu effect: A tool to determine stellar distances

The Wilson–Bappu effect: A tool to determine stellar distances

Evidence for radio emission from the giant binary lam and and a search for emission from other stars.

Late-Type Ca II Emission-Line Stars in the Southern Hemisphere

Contact Info

Product

Resources

About