Journal of Astronomy and Space Sciences

The Korean Space Science Society (한국우주과학회)
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Chemical Composition of RR Lyn - an Eclipsing Binary System with Am and λ Boo Type Components

  • Jeong, Yeuncheol (Faculty of General Education, Sejong University) ;
  • Yushchenko, Alexander V. (Department of Astronomy and Space Science, Sejong University) ;
  • Doikov, Dmytry N. (Department of Mathematics, Physics and Astronomy, Odessa National Maritime University) ;
  • Gopka, Vira F. (Astronomical Observatory, Odessa National University) ;
  • Yushchenko, Volodymyr O. (Astronomical Observatory, Odessa National University)
  • Received : 2017.04.14
  • Accepted : 2017.05.18
  • Published : 2017.06.15
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Abstract

High-resolution spectroscopic observations of the eclipsing binary system RR Lyn were made using the 1.8 m telescope at the Bohuynsan Optical Astronomical Observatory in Korea. The spectral resolving power was R = 82,000, with a signal to noise ratio of S/N > 150. We found the effective temperatures and surface gravities of the primary and secondary components to be equal to $T_{eff}$ = 7,920 & 7,210 K and log(g) = 3.80 & 4.16, respectively. The abundances of 34 and 17 different chemical elements were found in the atmospheric components. Correlations between the derived abundances with condensation temperatures and the second ionization potentials of these elements are discussed. The primary component is a typical metallic line star with the abundances of light and iron group elements close to solar values, while elements with atomic numbers Z > 30 are overabundant by 0.5-1.5 dex with respect to solar values. The secondary component is a ${\lambda}$ Boo type star. In this type of stars, CNO abundances are close to solar values, while the abundance pattern shows a negative correlation with condensation temperatures.

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