ACCURATE MASSES FOR THE PRIMARY AND SECONDARY IN THE ECLIPSING WHITE DWARF BINARY NLTT 11748

Journal Article · Fri Oct 01 00:00:00 EDT 2010 · Astrophysical Journal Letters

DOI:https://doi.org/10.1088/2041-8205/721/2/L158· OSTI ID:21452774

Kilic, Mukremin; Brown, Warren R; Kenyon, S J ^[1]; Allende Prieto, Carlos ^[2]; Agueeros, M A; Camilo, Fernando ^[3]

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1. Smithsonian Astrophysical Observatory, 60 Garden St., Cambridge, MA 02138 (United States)
2. Instituto de Astrofisica de Canarias, 38205 La Laguna, Tenerife (Spain)
3. Department of Astronomy, Columbia University, 550 West 120th Street, New York, NY 10027 (United States)

We measure the radial velocity curve of the eclipsing detached white dwarf binary NLTT 11748. The primary exhibits velocity variations with a semi-amplitude of 273 km s{sup -1} and an orbital period of 5.641 hr. We do not detect any spectral features from the secondary star or any spectral changes during the secondary eclipse. We use our composite spectrum to constrain the temperature and surface gravity of the primary to be T {sub eff} = 8690 {+-} 140 K and log g = 6.54 {+-} 0.05, which correspond to a mass of 0.18 M {sub sun}. For an inclination angle of 89.{sup 0}9 derived from the eclipse modeling, the mass function requires a 0.76 M {sub sun} companion. The merger time for the system is 7.2 Gyr. However, due to the extreme mass ratio of 0.24, the binary will most likely create an AM CVn system instead of a merger.

• OSTI ID: 21452774
• Journal Information: Astrophysical Journal Letters, Vol. 721, Issue 2; Other Information: DOI: 10.1088/2041-8205/721/2/L158; ISSN 2041-8205
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ECLIPSE
GRAVITATION
MASS
RADIAL VELOCITY
WHITE DWARF STARS
DWARF STARS
STARS
VELOCITY