The physical properties of double degenerate common proper motion binaries

Journal Article · Mon Apr 01 00:00:00 EST 1991 · Astronomical Journal; (USA)

DOI:https://doi.org/10.1086/115779· OSTI ID:5544466

Sion, E M; Oswalt, T D; Liebert, J; Hintzen, P ^[1]

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1. Observatoire Midi-Pyrenees, Toulouse (France) Villanova Univ., PA (USA) Florida Institute of Technology, Melbourne (USA) Steward Observatory, Tucson, AZ (USA) Nevada Univ., Las Vegas (USA)

Spectral types and spectrophotometry are presented for 21 double degenerate (DD) common proper motion binaries, along with estimates of their colors, absolute visual and bolometric magnitudes, and cooling ages. The oldest pairs in the sample are 9 x 10 to the 9th yr; the differential cooling ages range from 0.01 to 0.84. The median and mean separations of the DD pairs are 426 and 407 Au, respectively, both apparently smaller than the WD+MS values. The average UVW motions and velocity dispersions are significantly larger than the average velocities and dispersions associated with selected samples of single white dwarfs and MS+WD binaries when the latter are restricted to the same color/Mv range as the DD systems. This may be a result of the dynamical inflation of the velocity dispersion of DD systems due to their extremely ancient total stellar ages. 24 refs.

• OSTI ID: 5544466
• Journal Information: Astronomical Journal; (USA), Vol. 101; ISSN 0004-6256
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BINARY STARS
PHYSICAL PROPERTIES
AGE ESTIMATION
COLOR
COOLING
MAIN SEQUENCE STARS
MATTER
MOTION
SPECTROPHOTOMETRY
STAR EVOLUTION
WHITE DWARF STARS
DWARF STARS
OPTICAL PROPERTIES
ORGANOLEPTIC PROPERTIES
STARS
640102* - Astrophysics & Cosmology- Stars & Quasi-Stellar
Radio & X-Ray Sources