The Puzzling White Dwarf Cooling Sequence in NGC6791: A Simple Solution

Abstract

In this paper we demonstrate that the puzzling bright peak in the luminosity function of the white dwarf (WD) cooling sequence of NGC6791 can be naturally accounted for if ~34% of the observed WDs are WD+WD binary systems.

12 pages, 3 figures. Accepted (April 9th 2008) on ApJ Letter

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Cited by in corpus (54)

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• A white dwarf cooling age of 8 Gyr for NGC 6791 from physical separation processes
• Age and helium content of the open cluster NGC 6791 from multiple eclipsing binary members. II. age dependencies and new insights
• Multiple stellar populations in Magellanic Clouds clusters. I. An ordinary feature for intermediate age globulars in the LMC?
• Hubble Space Telescope reveals multiple Sub-Giant Branch in eight Globular Clusters
• On type Ia supernovae and the formation of single low-mass white dwarfs
• The End of the White Dwarf Cooling Sequence in M4: an efficient approach
• Chemical Composition of Faint (I~21 mag) Microlensed Bulge Dwarf OGLE-2007-BLG-514S
• Sodium and Oxygen Abundances in the Open Cluster NGC 6791 from APOGEE H-Band Spectroscopy
• The Galactic Gravitational wave foreground
• High resolution optical spectroscopy of Praesepe white dwarfs
• The Star Formation History of the Solar Neighbourhood from the White Dwarf Luminosity Function
• An upper limit to the secular variation of the gravitational constant from white dwarf stars
• Fast Winds and Mass Loss from Metal-Poor Field Giants
• The end of the white dwarf cooling sequence in M 67
• Evolution and colors of helium-core white dwarf stars with high-metallicity progenitors
• Pulsations in Hydrogen Burning Low Mass Helium White Dwarfs
• An accurate mass and radius measurement for an ultracool white dwarf
• The bottom of the white dwarf cooling sequence in the old open cluster NGC 2158
• A Double White-Dwarf Cooling Sequence in ω Centauri
• Spitzer Space Telescope evidence in NGC 6791: no super-mass-loss at super-solar metallicity to explain helium white dwarfs?
• Multiple stellar populations in Magellanic Cloud clusters. II. Evidence also in the young NGC1844?
• The White Dwarf Age of NGC 2477
• A comparative analysis of the observed white dwarf cooling sequence from globular clusters
• First Detection of the White-Dwarf Cooling Sequence of the Galactic Bulge
• The white dwarf population of NGC 6397
• White dwarfs as Physics laboratories: lights and shadows
• The white dwarf cooling sequence of 47 Tucanae
• Hubble Space Telescope observations of the Kepler-field cluster NGC 6819. I. The bottom of the white dwarf cooling sequence
• Stellar lifetime and ultraviolet properties of the old metal-rich Galactic open cluster NGC6791: a pathway to understand the UV upturn of elliptical galaxies
• Binary stars and the UVX in early type galaxies
• A Chandra X-ray study of the interacting binaries in the old open cluster NGC6791
• Revisiting binary stars in population synthesis models
• Uncovering the formation of ultra-compact dwarf galaxies by multivariate statistical analysis
• The X-ray Emissivity of Low-Density Stellar Populations
• Ensemble Properties of the White Dwarf Population of the Old, Solar Metallicity Open Star Cluster Messier 67
• The white dwarf cooling sequence of NGC 6791: a unique tool for stellar evolution
• The Distances to Open Clusters from Main-Sequence Fitting. V. Extension of Color Calibration and Test using Cool and Metal-Rich Stars in NGC 6791
• Star Cluster Ages in the Gaia Era
• The HST Large Programme on NGC 6752. III. Detection of the Peak of the White Dwarf Luminosity Function
• Analysis of the CN and CH molecular band strengths in stars of the open cluster NGC 6791
• A Spitzer Search for Substellar Companions to Low Mass White Dwarfs
• The longevity of the oldest open clusters: Structural parameters of NGC 188, NGC 2420, NGC 2425, NGC 2682, NGC 6791, NGC 6819
• A Turnoff Detached Binary Star V568 Lyr in the Kepler Field of the Oldest Open Cluster (NGC 6791) in the Galaxy
• Ne22 distillation and the cooling sequence of the old metal-rich open cluster NGC 6791
• A Chandra Survey of Milky Way Globular Clusters II: Testing the Hills-Heggie Law
• UB CCD photometry of the old, metal rich, open clusters NGC 6791, NGC 6819 and NGC 7142
• Pulsations of the Low Mass ZZ Ceti Star HS 1824+6000
• The Next Generation Virgo Cluster Survey. XXVIII. Characterization of the Galactic White Dwarf Population
• Binarity as the solution to the stellar evolution enigma posed by NGC 6791
• A deep HST view of the open cluster NGC2158: binaries, mass functions, and M-dwarf discontinuity
• Open clusters: probes of galaxy evolution and bench tests of stellar models