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arXiv · 1810.08444

Elemental Abundance Analysis of Single and Binary Late-B Stars Using Sub-meter Class Telescopes: HR 342, HR 769, HR 1284, and HR 8705

T. Kılıçoğlu·R. Monier
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Abstract

We test the capabilities of 0.4 m telescopes equipped with an \'{e}chelle spectrograph to derive fundamental parameters and elemental abundances of four late-B type stars: HR 342, HR 769, HR 1284, and HR 8705. The medium resolution (R~14000) spectra covering the wavelength range of 4380-7350 {\AA} of the four stars have been obtained using the 40-cm-telescope in Ankara University Kreiken Observatory (AUKR). Using spectrum synthesis, we were able to derive the abundances of eleven chemical elements. We find that these stars do not show remarkable departures from the solar abundances, except for HR 8705 and the primary component of HR 1284, which exhibit slight underabundances of a few elements, i.e., O, Mg, Al, Si, and Fe. We also find that HR 1284 is probably a new spectroscopic binary star. In order to model the spectrum of this object, one of us (TK) has developed a new graphic interface which allows us to synthesize the composite spectrum of binary stars.

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T. Kılıçoğlu, R. Monier. 2018-10-19. Elemental Abundance Analysis of Single and Binary Late-B Stars Using Sub-meter Class Telescopes: HR 342, HR 769, HR 1284, and HR 8705. https://arxiv.org/abs/1810.08444

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