Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Discipline
Articles 1 - 2 of 2
Full-Text Articles in Physical Sciences and Mathematics
The Eclipsing Binary V1061 Cygni: Confronting Stellar Evolution Models For Active And Inactive Solar-Type Stars, Guillermo Torres, Claud H. Sandberg Lacy, Laurence A. Marschall, Holly A. Sheets, Jeff A. Mader
The Eclipsing Binary V1061 Cygni: Confronting Stellar Evolution Models For Active And Inactive Solar-Type Stars, Guillermo Torres, Claud H. Sandberg Lacy, Laurence A. Marschall, Holly A. Sheets, Jeff A. Mader
Physics and Astronomy Faculty Publications
We present spectroscopic and photometric observations of the chromospherically active (X-ray strong) eclipsing binary V1061 Cyg (P = 2.35 days) showing that it is in reality a hierarchical triple system. We combine these observations with Hipparcos intermediate data (abscissa residuals) to derive the outer orbit with a period of 15.8 yr. We determine accurate values for the masses, radii, and effective temperatures of the eclipsing binary components, as well as for the mass and temperature of the third star. For the primary we obtain M = 1.282 ± 0.015 M⊙, R = 1.615 ± 0.017 R⊙, Teff = 6180 ± …
Measuring Inter-Dna Potentials In Solution, Xiangyun Qiu, Lisa W. Kwok, Hye Yoon Park, Jessica S. Lamb, Kurt Andresen, Lois Pollack
Measuring Inter-Dna Potentials In Solution, Xiangyun Qiu, Lisa W. Kwok, Hye Yoon Park, Jessica S. Lamb, Kurt Andresen, Lois Pollack
Physics and Astronomy Faculty Publications
Interactions between short strands of DNA can be tuned from repulsive to attractive by varying solution conditions and have been quantified using small angle x-ray scattering techniques. The effective DNA interaction charge was extracted by fitting the scattering profiles with the generalized one-component method and inter-DNA Yukawa pair potentials. A significant charge is measured at low to moderate monovalent counterion concentrations, resulting in strong inter-DNA repulsion. The charge and repulsion diminish rapidly upon the addition of divalent counterions. An intriguing short range attraction is observed at surprisingly low divalent cation concentrations, ~16 mM Mg2+. Quantitative measurements of inter- DNA potentials …