Bibcode
Eikenberry, S. S.; Chojnowski, S. Drew; Wisniewski, John; Majewski, Steven R.; Shetrone, Matthew; Whelan, David G.; Bizyaev, Dmitry; Borish, H. Jacob; Davenport, James R. A.; Ebelke, Garrett; Feuillet, Diane; Frinchaboy, Peter M.; Garner, Alan; Hearty, Fred; Holtzman, Jon; Li, Zhi-Yun; Mészáros, Sz.; Nidever, David L.; Schneider, Donald P.; Skrutskie, Michael; Wilson, John C.; Zasowski, Gail
Referencia bibliográfica
The Astrophysical Journal Letters, Volume 784, Issue 2, article id. L30, 5 pp. (2014).
Fecha de publicación:
4
2014
Número de citas
27
Número de citas referidas
25
Descripción
The Apache Point Observatory Galactic Evolution Experiment
(APOGEE)—one of the Sloan Digital Sky Survey III programs—is
using near-infrared (NIR) spectra of ~100,000 red giant branch star
candidates to study the structure of the Milky Way. In the course of the
survey, APOGEE also acquires spectra of hot field stars to serve as
telluric calibrators for the primary science targets. We report the
serendipitous discovery of two rare, fast-rotating B-stars of the
σ Ori E type among those blue field stars observed during the
first year of APOGEE operations. Both of the discovered stars display
the spectroscopic signatures of rigidly rotating magnetospheres (RRM)
common to this class of highly magnetized (B ~ 10 kGauss) stars,
increasing the number of known RRM stars by ~10%. One (HD 345439) is a
main-sequence B-star with unusually strong He absorption (similar to
σ Ori E), while the other (HD 23478) fits a "He-normal" B3IV
classification. We combine the APOGEE discovery spectra with other
optical and NIR spectra of these two stars, and of σ Ori E itself,
to show how NIR spectroscopy can be a uniquely powerful tool for
discovering more of these rare objects, which may show little/no RRM
signatures in their optical spectra. We discuss the potential for
further discovery of σ Ori E type stars, as well as the
implications of our discoveries for the population of these objects and
insights into their origin and evolution.
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