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Title: THE KEPLER LIGHT CURVE OF THE UNIQUE DA WHITE DWARF BOKS 53856

Abstract

The faint (g = 16.9) hot white dwarf BOKS 53856 was observed by the Kepler Mission in short cadence mode during mid-2009. Analysis of these observations reveals a highly stable modulation with a period of 6.1375 hr and a 2.46% half-amplitude. The folded light curve has an unusual shape that is difficult to explain in terms of a binary system containing an unseen companion more luminous than an L0 brown dwarf. Optical spectra of BOKS 53856 show a T{sub eff} = 34,000 K, log g = 8.0 DA white dwarf. There are few, if any, known white dwarfs in this temperature range exhibiting photometric variations similar to those we describe. A magnetic spin-modulated white dwarf model can in principle explain the light curve, an interpretation supported by spectral observations of the H{alpha} line showing evidence of Zeeman splitting.

Authors:
 [1];  [2]
  1. Lunar and Planetary Laboratory, 1541 E. University Blvd, Sonett Space Sciences Building, University of Arizona, Tucson, AZ 85721 (United States)
  2. National Optical Astronomy Observatory, 950 N. Cherry Ave, Tucson, AZ 85719 (United States)
Publication Date:
OSTI Identifier:
21583002
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astronomical Journal (New York, N.Y. Online); Journal Volume: 142; Journal Issue: 2; Other Information: DOI: 10.1088/0004-6256/142/2/62
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; AMPLITUDES; SPIN; VISIBLE SPECTRA; WHITE DWARF STARS; ZEEMAN EFFECT; ANGULAR MOMENTUM; DWARF STARS; PARTICLE PROPERTIES; SPECTRA; STARS

Citation Formats

Holberg, J. B., and Howell, Steve B., E-mail: holberg@argus.lpl.arizona.edu, E-mail: howell@noao.edu. THE KEPLER LIGHT CURVE OF THE UNIQUE DA WHITE DWARF BOKS 53856. United States: N. p., 2011. Web. doi:10.1088/0004-6256/142/2/62.
Holberg, J. B., & Howell, Steve B., E-mail: holberg@argus.lpl.arizona.edu, E-mail: howell@noao.edu. THE KEPLER LIGHT CURVE OF THE UNIQUE DA WHITE DWARF BOKS 53856. United States. doi:10.1088/0004-6256/142/2/62.
Holberg, J. B., and Howell, Steve B., E-mail: holberg@argus.lpl.arizona.edu, E-mail: howell@noao.edu. 2011. "THE KEPLER LIGHT CURVE OF THE UNIQUE DA WHITE DWARF BOKS 53856". United States. doi:10.1088/0004-6256/142/2/62.
@article{osti_21583002,
title = {THE KEPLER LIGHT CURVE OF THE UNIQUE DA WHITE DWARF BOKS 53856},
author = {Holberg, J. B. and Howell, Steve B., E-mail: holberg@argus.lpl.arizona.edu, E-mail: howell@noao.edu},
abstractNote = {The faint (g = 16.9) hot white dwarf BOKS 53856 was observed by the Kepler Mission in short cadence mode during mid-2009. Analysis of these observations reveals a highly stable modulation with a period of 6.1375 hr and a 2.46% half-amplitude. The folded light curve has an unusual shape that is difficult to explain in terms of a binary system containing an unseen companion more luminous than an L0 brown dwarf. Optical spectra of BOKS 53856 show a T{sub eff} = 34,000 K, log g = 8.0 DA white dwarf. There are few, if any, known white dwarfs in this temperature range exhibiting photometric variations similar to those we describe. A magnetic spin-modulated white dwarf model can in principle explain the light curve, an interpretation supported by spectral observations of the H{alpha} line showing evidence of Zeeman splitting.},
doi = {10.1088/0004-6256/142/2/62},
journal = {Astronomical Journal (New York, N.Y. Online)},
number = 2,
volume = 142,
place = {United States},
year = 2011,
month = 8
}
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