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Full-Text Articles in Physical Sciences and Mathematics
Simultaneous Light And Radial Velocity Curve Solutions For U Cephei, James Bruce Rafert, N L. Markworth
Simultaneous Light And Radial Velocity Curve Solutions For U Cephei, James Bruce Rafert, N L. Markworth
Aerospace, Physics, and Space Science Faculty Publications
The light-curve synthesis approach of Wilson & Devinney has been used to solve simultaneously light and radial velocity curves of the Algol-type eclipsing binary star U Cephei. We have performed eight new differential corrections solutions using the photometric data of Markworth and the radial velocity data of Batten to obtain a consistent set of orbital and astrophysical parameters for the light and velocity curves of this famous system. We find U Cephei to be best modeled using the semidetached (mode 5) system geometry of the Wilson & Devinney program, with a primary rotating at about 5.2 times its synchronous rate, …
The Physical Properties Of Double Degenerate Common Proper Motion Binaries, Edward M. Sion, Terry D. Oswalt, James Liebert, Paul Hintsen
The Physical Properties Of Double Degenerate Common Proper Motion Binaries, Edward M. Sion, Terry D. Oswalt, James Liebert, Paul Hintsen
Aerospace, Physics, and Space Science Faculty Publications
We present spectral types and spectrophotometry for 21 double degenerate (DD) common proper motion binaries and provide estimates of their colors, absolute visual and bolometric magnitudes, and cooling ages. The most typical double degenerate pair contains stars of similar color and spectral type, with an average Mv = 14.20, and average cooling age of ≈3×10⁹ yr, thus typically belonging to the extremely old disk population subcomponent. The oldest pairs in the sample are 9 × 10⁹ yr. The differential cooling ages, Δ log τc, range between 0.01 and 0.84, with the most typical pair having Δ log τc = 0.30, …
Uv Observations Of The Cool Dbqa5 White Dwarf Lds 678a: Limits On The Atmospheric Composition, Pressure Shift, And Gravitational Redshift Derived From C I 2479, Terry D. Oswalt, Edward M. Sion, Gordon Hammond, James W. Liebert, Gary Wegner, Detlev Koester, Pamela M. Marcum
Uv Observations Of The Cool Dbqa5 White Dwarf Lds 678a: Limits On The Atmospheric Composition, Pressure Shift, And Gravitational Redshift Derived From C I 2479, Terry D. Oswalt, Edward M. Sion, Gordon Hammond, James W. Liebert, Gary Wegner, Detlev Koester, Pamela M. Marcum
Aerospace, Physics, and Space Science Faculty Publications
We present a high-resolution ultraviolet spectrum of the helium-rich degenerate LDS 678A, obtained with the International Ultraviolet Explorer (IUE) satellite. LDS 678A is the coolest metallic line degenerate (DQ or DZ) yet observed with the IUE echelle. These observations provide a detailed line profile of the strong C I 2479 absorption line and equivalent width W₂₄₇₉ = 2.35 ± 0.06 Å from which theoretical profile fits yield a carbon abundance of log C/He = (-6.7 ± 0.2). The presence of carbon in a Herich atmosphere lends credence to the notion that LDS 678A is a transitional case between the DB …