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Full-Text Articles in Physical Sciences and Mathematics
Kepler Eclipsing Binary Stars. Vii. The Catalog Of Eclipsing Binaries Found In The Entire Kepler Data Set, Brian Kirk, Darin Ragozzine
Kepler Eclipsing Binary Stars. Vii. The Catalog Of Eclipsing Binaries Found In The Entire Kepler Data Set, Brian Kirk, Darin Ragozzine
Aerospace, Physics, and Space Science Faculty Publications
The primary Kepler Mission provided nearly continuous monitoring of ∼200,000 objects with unprecedented photometric precision. We present the final catalog of eclipsing binary systems within the 105 deg2 Kepler field of view. This release incorporates the full extent of the data from the primary mission (Q0-Q17 Data Release). As a result, new systems have been added, additional false positives have been removed, ephemerides and principal parameters have been recomputed, classifications have been revised to rely on analytical models, and eclipse timing variations have been computed for each system. We identify several classes of systems including those that exhibit tertiary eclipse …
The White Dwarfs Within 25 Pc Of The Sun: Kinematics And Spectroscopic Subtypes, Edward M. Sion, Jay B. Holberg, Terry D. Oswalt, George P. Mccook, Richard Wasatonic, Janine Myszka
The White Dwarfs Within 25 Pc Of The Sun: Kinematics And Spectroscopic Subtypes, Edward M. Sion, Jay B. Holberg, Terry D. Oswalt, George P. Mccook, Richard Wasatonic, Janine Myszka
Aerospace, Physics, and Space Science Faculty Publications
We present the fractional distribution of spectroscopic subtypes, range and distribution of surface temperatures, and kinematical properties of the white dwarfs (WDs) within 25 pc of the Sun. There is no convincing evidence of halo WDs in the total 25 pc sample of 224 WDs. There is also little to suggest the presence of genuine thick disk subcomponent members within 25 pc. It appears that the entire 25 pc sample likely belongs to the thin disk. We also find no significant kinematic differences with respect to spectroscopic subtypes. The total DA to non-DA ratio of the 25 pc sample is …
Exploring The Variable Sky With Linear. Iii. Classification Of Periodic Light Curves, Lovro Palaversa, Hakeem Oluseyi
Exploring The Variable Sky With Linear. Iii. Classification Of Periodic Light Curves, Lovro Palaversa, Hakeem Oluseyi
Aerospace, Physics, and Space Science Faculty Publications
We describe the construction of a highly reliable sample of ∼7000 optically faint periodic variable stars with light curves obtained by the asteroid survey LINEAR across 10,000 deg2 of the northern sky. The majority of these variables have not been cataloged yet. The sample flux limit is severalmagnitudes fainter than most other wide-angle surveys; the photometric errors range from ∼0.03 mag at r = 15 to ∼0.20 mag at r = 18. Light curves include on average 250 data points, collected over about a decade. Using Sloan Digital Sky Survey (SDSS) based photometric recalibration of the LINEAR data for about …
The White Dwarfs Within 20 Parsecs Of The Sun: Kinematics And Statistics, Edward M. Sion, Jay B. Holberg, Terry D. Oswalt, George P. Mccook, Richard Wasatonic
The White Dwarfs Within 20 Parsecs Of The Sun: Kinematics And Statistics, Edward M. Sion, Jay B. Holberg, Terry D. Oswalt, George P. Mccook, Richard Wasatonic
Aerospace, Physics, and Space Science Faculty Publications
We present the kinematical properties, distribution of spectroscopic subtypes, and stellar population subcomponents of the white dwarfs within 20 pc of the Sun. We find no convincing evidence of halo white dwarfs in the total 20 pc sample of 129 white dwarfs nor is there convincing evidence of genuine thick disk subcomponent members within 20 parsecs. Virtually, the entire 20 pc sample likely belongs to the thin disk. The total DA to non-DA ratio of the 20 pc sample is 1.6, a manifestation of deepening envelope convection which transforms DA stars with sufficiently thin H surface layers into non-DAs. The …
A New Look At The Local White Dwarf Population, Jay B. Holberg, Edward M. Sion, Terry D. Oswalt, George P. Mccook, S Foran, John P. Subasavage
A New Look At The Local White Dwarf Population, Jay B. Holberg, Edward M. Sion, Terry D. Oswalt, George P. Mccook, S Foran, John P. Subasavage
Aerospace, Physics, and Space Science Faculty Publications
We have conducted a detailed new survey of the local population of white dwarfs lying within 20 pc of the Sun. A new revised catalog of local white dwarfs containing 122 entries (126 individual degenerate stars) is presented. This list contains 27 white dwarfs not included in a previous list from 2002, as well as new and recently published trigonometric parallaxes. In several cases new members of the local white dwarf population have come to light through accurate photometric distance estimates. In addition, a suspected new double degenerate system (WD 0423+120) has been identified. The 20 pc sample is currently …
A Determination Of The Local Density Of White Dwarf Stars, Jay B. Holberg, Terry D. Oswalt, Edward M. Sión
A Determination Of The Local Density Of White Dwarf Stars, Jay B. Holberg, Terry D. Oswalt, Edward M. Sión
Aerospace, Physics, and Space Science Faculty Publications
The most recent version of the Catalog of Spectroscopically Identified White Dwarfs lists 2249 white dwarf stars. Among these stars are 109 white dwarfs that have either reliable trigonometric parallaxes or color-based distance moduli that place them at a distance within 20 pc of the Sun. Most of these nearby white dwarfs are isolated stars, but 28 (25% of the sample) are in binary systems, including such well-known systems as Sirius A/B and Procyon A/B. There are also three double degenerate systems in this sample of the local white dwarf population. The sample of local white dwarfs is largely complete …
White Dwarf Cosmochronometry. I. Monte Carlo Simulations Of Proper-Motion And Magnitude-Limited Samples Using Schmidt's 1/Vmax Estimator, Matt A. Wood, Terry D. Oswalt
White Dwarf Cosmochronometry. I. Monte Carlo Simulations Of Proper-Motion And Magnitude-Limited Samples Using Schmidt's 1/Vmax Estimator, Matt A. Wood, Terry D. Oswalt
Aerospace, Physics, and Space Science Faculty Publications
Observationally, white dwarf stars are a remarkably homogeneous class with a minimum observed Teff ∼ 4000 K. Theoretically, the physics that determines their cooling timescales is relatively more straightforward than that which determines main-sequence evolutionary timescales. As a result, the white dwarf luminosity function has for the last decade been used as a probe of the age and star formation rate of the Galactic disk, providing an estimated local disk age of ∼ 10 Gyr with estimated total uncertainties of roughly 20%. A long-standing criticism of the technique is that the reality of the reported downturn in the luminosity function …
White Dwarfs In Globular Clusters: Hubble Space Telescope Observations Of M4, Harvey B. Richer, Matt A. Wood
White Dwarfs In Globular Clusters: Hubble Space Telescope Observations Of M4, Harvey B. Richer, Matt A. Wood
Aerospace, Physics, and Space Science Faculty Publications
Using WFPC2 on the Hubble Space Telescope, we have isolated a sample of 258 white dwarfs (WDs) in the Galactic globular cluster M4. Fields at three radial distances from the cluster center were observed, and sizable WD populations were found in all three. The location of these WDs in the color-magnitude diagram, their mean mass of 0.51(±0.03) M⊙, and their luminosity function confirm basic tenets of stellar evolution theory and support the results from current WD cooling theory. The WDs are used to extend the cluster main-sequence mass function upward to stars that have already completed their nuclear evolution. The …