Coordinated optical and ultraviolet observations of DH Leo

Newmark, J S; Buzasi, D L; Huenemoerder, D P; Ramsey, L W; Barden, S C

doi:10.1086/115539

Title: Coordinated optical and ultraviolet observations of DH Leo

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Abstract

Results are reported from contemporaneous KPNO optical spectroscopy, IUE UV spectroscopy, and KPNO R photometry of the DH Leo triple system in spring 1987. The data are presented in tables, graphs, and spectral phase images and discussed in detail. The H-alpha, H-beta, H-gamma, H-delta, and Ca II H and IRT lines are found to have excess emission, and the phase modulation in H-alpha, H-beta, and Ca II is well correlated with the photometric modulation. This result is attributed to the combination of (1) a small amount of global chromospheric emission and (2) emission from plagelike regions associated with cool starspots. The (H-alpha)/(H-beta) ratio is found to be significantly lower than that in longer-period RS CVn systems. 22 refs.

Authors:

Newmark, J S; Buzasi, D L; Huenemoerder, D P; Ramsey, L W; Barden, S C ^[1]

Pennsylvania State Univ., University Park (USA) Kitt Peak National Observatory, Tucson, AZ (USA)

Publication Date:: Wed Aug 01 00:00:00 EDT 1990

OSTI Identifier:: 6439910

Resource Type:: Journal Article

Journal Name:: Astronomical Journal; (USA)

Additional Journal Information:: Journal Volume: 100; Journal ID: ISSN 0004-6256

Country of Publication:: United States

Language:: English

Subject:: 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BINARY STARS; ULTRAVIOLET SPECTRA; VISIBLE SPECTRA; BALMER LINES; EMISSION SPECTRA; GRAPHS; IMAGES; MORPHOLOGY; PHOTOMETRY; SPECTROSCOPY; STARSPOTS; TABLES; SPECTRA; STARS; STELLAR ACTIVITY; 640102* - Astrophysics & Cosmology- Stars & Quasi-Stellar, Radio & X-Ray Sources

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                    Newmark, J S, Buzasi, D L, Huenemoerder, D P, Ramsey, L W, and Barden, S C. Coordinated optical and ultraviolet observations of DH Leo.  United States: N. p., 1990. 
        Web.  doi:10.1086/115539.

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                    Newmark, J S, Buzasi, D L, Huenemoerder, D P, Ramsey, L W, & Barden, S C. Coordinated optical and ultraviolet observations of DH Leo.  United States.  https://doi.org/10.1086/115539

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                    Newmark, J S, Buzasi, D L, Huenemoerder, D P, Ramsey, L W, and Barden, S C. 1990.  
        "Coordinated optical and ultraviolet observations of DH Leo".  United States.  https://doi.org/10.1086/115539.

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@article{osti_6439910,

  title        = {Coordinated optical and ultraviolet observations of DH Leo},

  author       = {Newmark, J S and Buzasi, D L and Huenemoerder, D P and Ramsey, L W and Barden, S C},

  abstractNote = {Results are reported from contemporaneous KPNO optical spectroscopy, IUE UV spectroscopy, and KPNO R photometry of the DH Leo triple system in spring 1987. The data are presented in tables, graphs, and spectral phase images and discussed in detail. The H-alpha, H-beta, H-gamma, H-delta, and Ca II H and IRT lines are found to have excess emission, and the phase modulation in H-alpha, H-beta, and Ca II is well correlated with the photometric modulation. This result is attributed to the combination of (1) a small amount of global chromospheric emission and (2) emission from plagelike regions associated with cool starspots. The (H-alpha)/(H-beta) ratio is found to be significantly lower than that in longer-period RS CVn systems. 22 refs.},

  doi          = {10.1086/115539},

  url          = {https://www.osti.gov/biblio/6439910},
  journal      = {Astronomical Journal; (USA)},

  issn         = {0004-6256},

  number       = ,

  volume       = 100,

  place        = {United States},

  year         = {Wed Aug 01 00:00:00 EDT 1990},

  month        = {Wed Aug 01 00:00:00 EDT 1990}

}

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